HD AI suddenly really hard?

I usually play standard ai and occasionally moderate with friends. When we played standard, we could walk all over them, but for some reason lately the ai have been pretty difficult, even just on standard. They now rush pretty early on with a decent army, whereas before they used to hardly attack before at least castle. They feel like moderates. I've tried this on both original and the new ai in HD and it seems to happen either way. Was there some way I accidentally changed ai behavior, or was there an update or something that affected ai? I have no clue why standard ai is suddenly so difficult when they used to be a cake walk for me....