diff --git a/build-bin/docker/configure_docker_push b/build-bin/docker/configure_docker_push
index 149ff90..196e302 100755
--- a/build-bin/docker/configure_docker_push
+++ b/build-bin/docker/configure_docker_push
@@ -13,7 +13,7 @@
 # the License.
 #
 
-# Ensures Docker is logged in, buildx is available and it can build multi-architecture.
+# Ensures Docker is logged in and it can build multi-architecture.
 # This should be used instead of `configure_docker` when a push will occur.
 #
 # This should only happen when we are publishing multi-arch builds, as otherwise the setup could use
@@ -32,7 +32,7 @@ fi
 echo '{ "experimental":true, "registry-mirrors": ["https://mirror.gcr.io"] }' | sudo tee /etc/docker/daemon.json
 
 sudo service docker restart
-# Enable experimental client features (eg docker buildx)
+# Enable experimental client features (multi-arch)
 mkdir -p ${HOME}/.docker && echo '{"experimental":"enabled"}' > ${HOME}/.docker/config.json
 
 # Log in to GitHub Container Registry and Docker Hub for releasing images
diff --git a/build-bin/docker/docker_arch b/build-bin/docker/docker_arch
index 1d86236..c668e69 100755
--- a/build-bin/docker/docker_arch
+++ b/build-bin/docker/docker_arch
@@ -20,24 +20,24 @@
 
 set -ue
 
-# Normalize arch to what's available
-arch=${ARCH:-$(uname -m)}
-case ${arch} in
+# Normalize docker_arch to what's available
+docker_arch=${DOCKER_ARCH:-$(uname -m)}
+case ${docker_arch} in
   amd64* )
-    arch=amd64
+    docker_arch=amd64
     ;;
   x86_64* )
-    arch=amd64
+    docker_arch=amd64
     ;;
   arm64* )
-    arch=arm64
+    docker_arch=arm64
     ;;
   aarch64* )
-    arch=arm64
+    docker_arch=arm64
     ;;
   * )
-    >&2 echo "Unsupported arch: ${arch}"
+    >&2 echo "Unsupported DOCKER_ARCH: ${docker_arch}"
     exit 1;
 esac
 
-echo ${arch}
+echo ${docker_arch}
diff --git a/build-bin/docker/docker_build b/build-bin/docker/docker_build
index 9f52d7c..98c8e78 100755
--- a/build-bin/docker/docker_build
+++ b/build-bin/docker/docker_build
@@ -19,7 +19,8 @@ docker_tag=${1?full docker_tag is required. Ex openzipkin/zipkin:test}
 version=${2:-}
 docker_args=$($(dirname "$0")/docker_args ${version})
 
-# Avoid buildx on load for two reasons:
+# Avoid buildx on load for reasons including:
+#  * Caching is more complex as builder instances must be considered
 #  * It only supports one platform/arch on load https://github.com/docker/buildx/issues/59
 #  * It would pull Docker Hub for moby/buildkit or multiarch/qemu-user-static images, using up quota
 echo "Building image ${docker_tag}"
diff --git a/build-bin/docker/docker_push b/build-bin/docker/docker_push
index 3d1f196..e4a3223 100755
--- a/build-bin/docker/docker_push
+++ b/build-bin/docker/docker_push
@@ -18,7 +18,11 @@
 # When a release, and DOCKER_RELEASE_REPOS is unset they also push to Docker Hub (docker.io).
 #
 # Note: In CI, `configure_docker_push` must be called before invoking this.
-
+#
+# Avoid buildx on push for reasons including:
+#  * Caching is more complex as builder instances must be considered
+#  * Platform builds run in parallel, leading to port conflict failures (ex in cassandra)
+#  * 0.4.2 multi-platform builds have failed due to picking the wrong image for a FROM instruction
 set -ue
 
 docker_image=${1?docker_image is required, notably without a tag. Ex openzipkin/zipkin}
@@ -60,7 +64,7 @@ for repo in ${docker_repos}; do
 done
 
 docker_args=$($(dirname "$0")/docker_args ${version})
-docker_archs=${DOCKER_PLATFORMS:-amd64 arm64}
+docker_archs=${DOCKER_ARCHS:-amd64 arm64}
 
 echo "Will build the following architectures: ${docker_archs}"