We have partially transparent chisels and bits over several redstone lamps. When these lamps are turned on and then off with a lever, the chiseled bits stay lit. After breaking and replacing one piece, the ones around it all update to the correct state, but then when the lever is activated they may stay unlit as well.

Is this with the current version? ( no pending updates? )

Yes, 11.9

So this isn't FC? ( Jenkins Build 11.0.10 )

This is on a custom server, not FC, so we're using the latest from CurseForge.

Ok, it might be fixed then, need to publish a new build, in the mean time feel free to test with the FC build if you want too.

Would the fix be clientside only? I do not have access to update the server at the moment.

It is but the versions different so it'll probably complain

Ok, I'll get back to you when I can update. Thanks!