A number of nodes are doing this and sending lots of unnecessary updates. Possibly the associations are not set correctly (maybe you have duplicates?) or maybe these devices have some issue. This might not be related to the controller issue, but I would strongly suggest to look into the issue as it won’t help your system performance.
I Also went back to 1577, besides the problem, that whenever I restart the server the port for the stick is not found (a simple renaming of the thing is enough to get it back online), everything went back to operational state.
I don’t think the issue is related to the binding version since there haven’t really been changes in this area for a long time. Possibly the controller was playing up and needed resetting - if it wasn’t sending the radio ACK to the devices, this might also have caused the multiple repeats of the data we saw, and would also cause the transaction problems which ultimately caused the queue being full.