diff --git a/.travis.yml b/.travis.yml
index 72bd3a32..c0a7d965 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -16,10 +16,10 @@ python:
   - "3.7"
 
 addons:
-  postgresql: '9.5'
+  postgresql: '10'
   apt:
     packages:
-      - postgresql-9.5-postgis-2.4
+      - postgresql-10-postgis-2.4
 
 install:
   - pip install -U pip
@@ -33,7 +33,7 @@ script:
   - python manage.py makemigrations --dry-run --check
   - black --check .
   - flake8
-  - isort --check-only --diff
+  - isort . --check-only --diff
   - pytest -ra -vvv --doctest-modules --cov=.
   - ./run-type-checks
 
diff --git a/batchrun/.isort.cfg b/batchrun/.isort.cfg
deleted file mode 100644
index 97824efe..00000000
--- a/batchrun/.isort.cfg
+++ /dev/null
@@ -1,5 +0,0 @@
-[isort]
-multi_line_output=4
-not_skip=__init__.py
-line_length=79
-known_standard_library=dataclasses
diff --git a/batchrun/admin.py b/batchrun/admin.py
index 9abfeec3..af36b5bb 100644
--- a/batchrun/admin.py
+++ b/batchrun/admin.py
@@ -1,4 +1,5 @@
 from django.contrib import admin
+from rangefilter.filter import DateRangeFilter  # type: ignore
 
 from .admin_utils import PreciseTimeFormatter, ReadOnlyAdmin
 from .models import (
@@ -23,14 +24,21 @@ class JobAdmin(admin.ModelAdmin):
     list_display = ["name", "comment", "command"]
 
 
+class JobRunLogEntryInline(admin.TabularInline):
+    model = JobRunLogEntry
+    show_change_link = True
+
+
 @admin.register(JobRun)
 class JobRunAdmin(ReadOnlyAdmin):
     date_hierarchy = "started_at"
+    inlines = [JobRunLogEntryInline]
     list_display = ["started_at_p", "stopped_at_p", "job", "exit_code"]
-    list_filter = ["exit_code"]
+    list_filter = ("started_at", ("started_at", DateRangeFilter), "job", "exit_code")
     # auto_now_add_fields don't show even in readonlyadmin.
     # Therefore we'll add all the fields by hand in a suitable order
     readonly_fields = ("job", "pid", "started_at_p", "stopped_at_p", "exit_code")
+    search_fields = ["log_entries__text"]
     exclude = ["stopped_at"]
 
     started_at_p = PreciseTimeFormatter(JobRun, "started_at")
diff --git a/batchrun/api/viewsets.py b/batchrun/api/viewsets.py
index 9ba35b04..393dfe6f 100644
--- a/batchrun/api/viewsets.py
+++ b/batchrun/api/viewsets.py
@@ -28,7 +28,7 @@ class Meta:
 
 
 class JobRunViewSet(viewsets.ReadOnlyModelViewSet):  # type: ignore
-    queryset = models.JobRun.objects.all()
+    queryset = models.JobRun.objects.all_with_deleted()  # type: ignore
     serializer_class = JobRunSerializer
     filterset_fields = ["exit_code"]
 
@@ -40,6 +40,6 @@ class Meta:
 
 
 class JobRunLogEntryViewSet(viewsets.ReadOnlyModelViewSet):  # type: ignore
-    queryset = models.JobRunLogEntry.objects.all()
+    queryset = models.JobRunLogEntry.objects.all_with_deleted()  # type: ignore
     serializer_class = JobRunLogEntrySerializer
     filterset_fields = ["run", "kind"]
diff --git a/batchrun/job_launching.py b/batchrun/job_launching.py
index 28e9fe36..aa8dd6df 100644
--- a/batchrun/job_launching.py
+++ b/batchrun/job_launching.py
@@ -30,7 +30,7 @@ def run_job(job: Job) -> JobRun:
     launcher = JobRunLauncher(job_run)
     launcher.start()
     launcher.join()
-    return job_run
+    return job_run  # type: ignore
 
 
 class JobRunLauncher(multiprocessing.Process):
diff --git a/batchrun/management/commands/batchrun_execute_job_run.py b/batchrun/management/commands/batchrun_execute_job_run.py
index b4efdef7..ccedd641 100644
--- a/batchrun/management/commands/batchrun_execute_job_run.py
+++ b/batchrun/management/commands/batchrun_execute_job_run.py
@@ -16,5 +16,5 @@ def add_arguments(cls, parser: argparse.ArgumentParser) -> None:
 
     def handle(self, *args: Any, **options: Any) -> None:
         job_run_id = options.get("job_run_id")
-        job_run = JobRun.objects.get(pk=job_run_id)  # type: ignore
+        job_run = JobRun.objects.get(pk=job_run_id)
         execute_job_run(job_run)
diff --git a/batchrun/management/commands/drop_old_log_entries.py b/batchrun/management/commands/drop_old_log_entries.py
index ad6f5540..8dad5788 100644
--- a/batchrun/management/commands/drop_old_log_entries.py
+++ b/batchrun/management/commands/drop_old_log_entries.py
@@ -4,7 +4,7 @@
 from dateutil.relativedelta import relativedelta
 from django.core.management.base import BaseCommand
 
-from ...models import JobRun, JobRunLogEntry
+from ...models import JobRun
 
 
 class Command(BaseCommand):
@@ -33,13 +33,6 @@ def handle(self, *args: Any, **options: Any) -> None:
                 JobRun.objects.count(),
             )
         )
-        log_entries_to_delete = JobRunLogEntry.objects.filter(
-            run__in=runs_before_cutoff
-        )
-        self.stdout.write(
-            "Proceeding to delete {} / {} stored JobRunLogEntries".format(
-                log_entries_to_delete.count(), JobRunLogEntry.objects.count()
-            )
-        )
-        log_entries_to_delete.delete()
+        runs_before_cutoff.delete()
+
         self.stdout.write("Done!")
diff --git a/batchrun/migrations/0002_add_safedelete_to_logs.py b/batchrun/migrations/0002_add_safedelete_to_logs.py
new file mode 100644
index 00000000..6061f134
--- /dev/null
+++ b/batchrun/migrations/0002_add_safedelete_to_logs.py
@@ -0,0 +1,34 @@
+# Generated by Django 2.2.13 on 2020-12-16 09:31
+
+import django.db.models.deletion
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("batchrun", "0001_initial"),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name="jobrun",
+            name="deleted",
+            field=models.DateTimeField(editable=False, null=True),
+        ),
+        migrations.AddField(
+            model_name="jobrunlogentry",
+            name="deleted",
+            field=models.DateTimeField(editable=False, null=True),
+        ),
+        migrations.AlterField(
+            model_name="jobrunlogentry",
+            name="run",
+            field=models.ForeignKey(
+                on_delete=django.db.models.deletion.CASCADE,
+                related_name="log_entries",
+                to="batchrun.JobRun",
+                verbose_name="run",
+            ),
+        ),
+    ]
diff --git a/batchrun/models.py b/batchrun/models.py
index eb8341a9..c6d10ba0 100644
--- a/batchrun/models.py
+++ b/batchrun/models.py
@@ -10,6 +10,7 @@
 from django.utils.translation import ugettext
 from django.utils.translation import ugettext_lazy as _
 from enumfields import EnumField
+from safedelete import SOFT_DELETE_CASCADE  # type: ignore
 from safedelete.models import SafeDeleteModel
 
 from ._times import utc_now
@@ -250,11 +251,13 @@ def update_run_queue(self, max_items_to_create: int = 10) -> None:
         items.exclude(pk__in=fresh_ids).delete()
 
 
-class JobRun(models.Model):
+class JobRun(SafeDeleteModel):
     """
     Instance of a job currently running or ran in the past.
     """
 
+    _safedelete_policy = SOFT_DELETE_CASCADE
+
     job = models.ForeignKey(Job, on_delete=models.PROTECT, verbose_name=_("job"))
     pid = models.IntegerField(
         null=True,
@@ -280,7 +283,7 @@ def __str__(self) -> str:
         return f"{self.job} [{self.pid}] ({self.started_at:%Y-%m-%dT%H:%M})"
 
 
-class JobRunLogEntry(models.Model):
+class JobRunLogEntry(SafeDeleteModel):
     """
     Entry in a log for a run of a job.
 
@@ -293,7 +296,7 @@ class JobRunLogEntry(models.Model):
 
     run = models.ForeignKey(
         JobRun,
-        on_delete=models.PROTECT,
+        on_delete=models.CASCADE,
         related_name="log_entries",
         verbose_name=_("run"),
     )
diff --git a/docker/postgres/Dockerfile b/docker/postgres/Dockerfile
index e5d0a718..441cbe0b 100644
--- a/docker/postgres/Dockerfile
+++ b/docker/postgres/Dockerfile
@@ -1,8 +1,8 @@
-FROM postgres:9.5
+FROM postgres:10.15
 
 RUN apt-get update \
     && apt-get install --no-install-recommends -y \
-        postgis postgresql-9.5-postgis-2.4 postgresql-9.5-postgis-2.4-scripts
+    postgis postgresql-10-postgis-2.4 postgresql-10-postgis-2.4-scripts
 
 RUN localedef -i fi_FI -c -f UTF-8 -A /usr/share/locale/locale.alias fi_FI.UTF-8
 
diff --git a/leasing/models/land_area.py b/leasing/models/land_area.py
index 9a6ad139..72519627 100644
--- a/leasing/models/land_area.py
+++ b/leasing/models/land_area.py
@@ -507,6 +507,25 @@ def save(self, *args, **kwargs):
         if self.id and not self.tracker.changed():
             return
 
+        # There can be only one master plan unit per lease area and identifier
+        if self.is_master:
+            master_plan_unit_count = (
+                PlanUnit.objects.filter(
+                    lease_area=self.lease_area,
+                    identifier=self.identifier,
+                    is_master=True,
+                )
+                .exclude(id=self.id)
+                .count()
+            )
+            if master_plan_unit_count:
+                raise Exception(
+                    _(
+                        "The master plan unit has already created. "
+                        "There can be only one master plan unit per lease area and identifier."
+                    )
+                )
+
         skip_modified_update = kwargs.pop("skip_modified_update", False)
         if skip_modified_update:
             modified_at_field = self._meta.get_field("modified_at")
diff --git a/leasing/serializers/invoice.py b/leasing/serializers/invoice.py
index 421c28b8..1338ff7f 100644
--- a/leasing/serializers/invoice.py
+++ b/leasing/serializers/invoice.py
@@ -62,8 +62,8 @@ def __init__(self, instance=None, data=empty, **kwargs):
         super().__init__(instance=instance, data=data, **kwargs)
 
         # Lease field must be added dynamically to prevent circular imports
-        from leasing.serializers.lease import LeaseSuccinctSerializer
         from leasing.models.lease import Lease
+        from leasing.serializers.lease import LeaseSuccinctSerializer
 
         self.fields["lease"] = InstanceDictPrimaryKeyRelatedField(
             instance_class=Lease,
@@ -507,8 +507,8 @@ def __init__(self, instance=None, data=empty, **kwargs):
         super().__init__(instance=instance, data=data, **kwargs)
 
         # Lease field must be added dynamically to prevent circular imports
-        from leasing.serializers.lease import LeaseSuccinctSerializer
         from leasing.models.lease import Lease
+        from leasing.serializers.lease import LeaseSuccinctSerializer
 
         self.fields["lease"] = InstanceDictPrimaryKeyRelatedField(
             instance_class=Lease,
diff --git a/leasing/tests/models/test_land_area.py b/leasing/tests/models/test_land_area.py
new file mode 100644
index 00000000..22c30afd
--- /dev/null
+++ b/leasing/tests/models/test_land_area.py
@@ -0,0 +1,19 @@
+import pytest
+
+
+@pytest.mark.django_db
+def test_plan_unit_cannot_create_another_master_plan_unit(
+    lease_test_data, plan_unit_factory
+):
+    master_plan_unit = plan_unit_factory(
+        area=100,
+        lease_area=lease_test_data["lease_area"],
+        identifier="1234",
+        is_master=True,
+    )
+
+    another_master_plan_unit = master_plan_unit
+    another_master_plan_unit.pk = None
+
+    with pytest.raises(Exception):
+        another_master_plan_unit.save()
diff --git a/locale/fi/LC_MESSAGES/django.po b/locale/fi/LC_MESSAGES/django.po
index b824274a..54500bea 100644
--- a/locale/fi/LC_MESSAGES/django.po
+++ b/locale/fi/LC_MESSAGES/django.po
@@ -7,7 +7,7 @@ msgid ""
 msgstr ""
 "Project-Id-Version: MVJ 0.1\n"
 "Report-Msgid-Bugs-To: \n"
-"POT-Creation-Date: 2020-11-23 11:25+0200\n"
+"POT-Creation-Date: 2021-01-07 15:34+0200\n"
 "PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n"
 "Last-Translator: \n"
 "Language: fi\n"
@@ -1693,6 +1693,11 @@ msgctxt "Model name"
 msgid "Plan units"
 msgstr "Kaavayksiköt"
 
+msgid ""
+"The master plan unit has already created. There can be only one master plan "
+"unit per lease area and identifier."
+msgstr "Alkuperäinen kaavayksikkö on jo luotu. Alkuperäisiä kaavayksiköitä voi olla vain yksi per vuokra-alueen kaavayksikön tunnus."
+
 msgid "Due dates position"
 msgstr "Eräpäivien sijainti"
 
@@ -1781,6 +1786,14 @@ msgstr "Maankäyttösopimukset"
 msgid "Estate id"
 msgstr "Kohteen tunniste"
 
+msgctxt "Model name"
+msgid "Land use agreement decision type"
+msgstr ""
+
+msgctxt "Model name"
+msgid "Land use agreement decision types"
+msgstr ""
+
 msgctxt "Model name"
 msgid "Land use agreement decision"
 msgstr "Maankäyttösopimus päätös"
@@ -1789,6 +1802,22 @@ msgctxt "Model name"
 msgid "Land use agreement decisions"
 msgstr "Maankäyttösopimus päätökset"
 
+msgctxt "Model name"
+msgid "Land use agreement decision condition type"
+msgstr ""
+
+msgctxt "Model name"
+msgid "Land use agreement decision condition types"
+msgstr ""
+
+msgctxt "Model name"
+msgid "Land use agreement decision condition"
+msgstr ""
+
+msgctxt "Model name"
+msgid "Land use agreement decision conditions"
+msgstr ""
+
 msgctxt "Model name"
 msgid "Land use agreement address"
 msgstr "Maankäyttösopimus osoite"
@@ -1797,11 +1826,17 @@ msgctxt "Model name"
 msgid "Land use agreement addresses"
 msgstr "Maankäyttösopimus osoitteet"
 
-msgid "Numerator"
-msgstr "Jaettava"
+msgid "Obligated area (f-m2)"
+msgstr ""
 
-msgid "Denominator"
-msgstr "Jakaja"
+msgid "Actualized area (f-m2)"
+msgstr ""
+
+msgid "Subvention amount"
+msgstr "Subvention määrä"
+
+msgid "Compensation percent"
+msgstr ""
 
 msgctxt "Model name"
 msgid "Land use agreement litigant"
@@ -2075,6 +2110,12 @@ msgctxt "Model name"
 msgid "Leasehold transfer properties"
 msgstr "Vuokraoikeuden siirron kohteet"
 
+msgid "Numerator"
+msgstr "Jaettava"
+
+msgid "Denominator"
+msgstr "Jakaja"
+
 msgctxt "Model name"
 msgid "Leasehold transfer party"
 msgstr "Vuokraoikeuden siirron osapuoli"
@@ -2302,9 +2343,6 @@ msgstr "Hallintamuoto (Subventio)"
 msgid "Rent adjustment"
 msgstr "Alennus/Korotus"
 
-msgid "Subvention amount"
-msgstr "Subvention määrä"
-
 msgctxt "Model name"
 msgid "Management subvention (Rent adjustment)"
 msgstr "Hallintamuotosubventio (Alennus)"
@@ -2831,12 +2869,12 @@ msgstr ""
 msgid "from_lease and to_lease cannot be the same Lease"
 msgstr "Ei voi olla sama vuokraus"
 
-msgid "The target information has changed!"
-msgstr "Kohteen tiedot ovat muuttuneet!"
-
 msgid "The target has been removed from the system!"
 msgstr "Kohde on poistunut järjestelmästä!"
 
+msgid "The target information has changed!"
+msgstr "Kohteen tiedot ovat muuttuneet!"
+
 msgid "Fixed initial rent end date must match rent cycle end date"
 msgstr "Alkuvuosivuokran loppu pitää olla sama kuin vuokrakauden loppu"
 
@@ -3054,6 +3092,15 @@ msgstr "Ei oikeutta lisätä muiden käyttäjien ui dataa"
 msgid "Data integrity error"
 msgstr "Tietoeheysvirhe"
 
+msgid "Finnish"
+msgstr "Suomi"
+
+msgid "Swedish"
+msgstr "Ruotsi"
+
+msgid "English"
+msgstr "Englanti"
+
 msgid "Sender email address. Example: john@example.com"
 msgstr "Lähettäjän sähköpostiosoite. Esimerkki: matti@example.com"
 
diff --git a/mvj/settings.py b/mvj/settings.py
index 9771b302..4ef4b21b 100644
--- a/mvj/settings.py
+++ b/mvj/settings.py
@@ -129,6 +129,7 @@ def get_git_revision_hash():
     "django.contrib.messages",
     "django.contrib.staticfiles",
     "django.contrib.gis",
+    "rangefilter",
     "helusers",
     "crispy_forms",
     "django_filters",
diff --git a/requirements-dev.txt b/requirements-dev.txt
index 84e41254..c8861d96 100644
--- a/requirements-dev.txt
+++ b/requirements-dev.txt
@@ -27,7 +27,7 @@ importlib-metadata==2.0.0  # via pluggy, pytest
 inflection==0.3.1         # via pytest-factoryboy
 ipython-genutils==0.2.0   # via traitlets
 ipython==7.13.0           # via -r requirements-dev.in
-isort==4.3.21             # via -r requirements-dev.in
+isort==5.6.4              # via -r requirements-dev.in
 jdcal==1.4.1              # via openpyxl
 jedi==0.16.0              # via ipython
 mccabe==0.6.1             # via flake8
diff --git a/requirements.in b/requirements.in
index eb4848be..368e6f34 100644
--- a/requirements.in
+++ b/requirements.in
@@ -3,6 +3,7 @@ dataclasses
 Django~=2.2.13
 django-anymail
 django-auditlog
+django-admin-rangefilter
 django-jsonfield-compat
 django-constance[database]
 django-cors-headers
diff --git a/requirements.txt b/requirements.txt
index 0b18598f..a2d39375 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -20,6 +20,7 @@ cryptography==3.2         # via paramiko
 database-sanitizer==1.1.0  # via django-sanitized-dump
 dataclasses==0.6          # via -r requirements.in
 defusedxml==0.6.0         # via zeep
+django-admin-rangefilter==0.6.3  # via -r requirements.in
 django-anymail==7.0.0     # via -r requirements.in
 django-auditlog==0.4.7    # via -r requirements.in
 django-constance[database]==2.7.0  # via -r requirements.in
diff --git a/setup.cfg b/setup.cfg
index 768c312c..cbc1caf7 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -24,7 +24,6 @@ multi_line_output=3
 line_length = 88
 include_trailing_comma = true
 skip=.tox,dist,venv,docs,migrations,.git
-not_skip=__init__.py
 
 [pydocstyle]
 ignore=D100,D104,D105,D200,D203,D400