High frequency commands and queue flush

[thingersoft]

Api version: 2.0.3
G2 firmware versione: 0.99
G2 firmware build: 101.03

After issuing a few command sequences followed by a feedhold+flush (!%) the communication stalls.
The G2 is still responding but subsequent commands won't make it to the device.
By a quick look there seems to be an issue with the api internal queues management.

Attached is a simple test case, after a few iterations you'll see no more status updates because commands aren't being transmitted to G2:
g2_flush_stall.zip