@o4kapuk Thanks. I'll start checking for any position assignments.

On shard1 room E36S58, when I run Game.rooms["E36S58"].controller.position, the engine returns the position of one of my creeps. This results in all of my upgraders following a creep around and clogging up what little space exists between the rocks. I'm also having the issue in room E37S57, but I don't have the problem in my first claimed room, E34S59.

I claimed these rooms just before the power creeps update. I don't remember having problems during that short time, but I'm definitely having problems since the power creeps update.