G. rosea question

[woody]

I just noticed that my G. rosea was laying flat on the substrate with its legs kinda stretched out. They weren't curled under so I wasn't really worried but I'm just wondering if anyone else has seen them do this before. It hasn't moulted since early January so I figured maybe it was some form of pre-moult behaviour that I hadn't witnessed before. Any ideas? It went right back to its normal position as soon as I loomed over the tank.