Could you maybe try adding a dummy item to bridge 2 to see if the problem appears on your side as well?
i am running out of ideas there … thank you!
regarding 5.0 snapshot - have you disabled “listen to network interface” via UI → homekit as on screenshot above?
by default, listen to network changes is enabled so that fix is not active.
i have also tried with multiple bridges on my side - running since 3 days without issues. but i have it not on Synology NAS / Docker but native on debian