Keep checking. Did you try online or call? I would definitely keep trying or try by plugging in different dates (e.g.starting one date earlier and dropping it later on). See if that changes the availability. Also try using hotels.com and other non-Disney room providers.
Yes, I am aware it is spring break and Easter vacation. What I meant is why do the other resorts still have standard rooms? Are there cheer or dance groups at ASMU that week?