Coming towards the end of the month, my internet usage runs out normally, I was lagging quite bad and just broke a whole bunch of blocks in the wastelands spawn and managed to see this, Whats this, anyone know? maybe something put by the admins
Sometimes, when you have a bad connection, but aren't disconnected, you can place and destroy blocks client-side, which means Minecraft on your computer thinks that you can build here, but the server is trying to tell the client you're not allowed to, which is interrupted via the bad connection. After your connection clears up/kicks you off, the server saves nothing you did and you are sent back to wherever you were before, as if nothing happened.
I saw that, too. I had a bad connection so I figured I'd see what was in spawn. I've got a picture of that.