Help Redstone not working with new update

Hello build community,

I've done a fair bit of building with redstone on your wonderful (1.8) server. I often use are pistons; i.e. a piston pushes a block into a circuit, and repeaters make the circuit travel through it.

Now, this was all very well and good until recently. I was building and noticed that the circuit acted 'complete' even when the block holding it together was removed -- the redstone was still powered somehow until it was broken. At first I thought this was a glitch, but I found that all of the circuits I've built on the server no longer work -- they are all affected by this problem.

Here is a video illustrating exactly what I mean:

Yes, I have tried relogging and reloading the map. I know there were some build updates recently, and this mechanic worked perfectly fine before the recent updates. Is there anything I can do?