Depending on time of year, my birds get 9-14 hours of sleep.
I don't believe that parrots must get 12 hours of sleep year round. In fact, I feel as if providing 12 hours of sleep year round may be setting some birds up for hormonal problems down the road.
But then, I don't necessarily agree to keeping parrots to a strict routine. If a bird becomes accustomed to routine and all of a sudden you change something, the bird might react negatively.... so why not spice things up and try and keep a little variety in their daily lives so that when something *is* different, it wont phase them?