Running into conflicts with new versions can be a pain. Have you tried checking the bbPress forums for similar issues with the new version and BuddyPress? There might be a workaround.
I feel you on the 700 clients! Hopefully a bbPress update is coming soon to address compatibility. In the meantime, BP Classic might be a temporary solution for some.
I’ve heard disabling plugins one by one and switching to a default theme can sometimes help with these AJAX functionality issues. Let me know if you try this and it works!
Whew, that’s a lot to catch up on! Thanks for the info, Milan. Updating bbPress now.