Hello cough
Which AA are you talking about? Lots of companies impose one (Ryanair for instance impose an MFRA of 1000 feet) and at Ryanair if you raise the flap before you have gone through that you'll get into trouble. But that's not a directive from Boeing. I have found a reference in the Boeing 737 classic training notes that suggests the minimum height for flap retraction is 400 feet but its the only manufacturers recommendations I can find.
If there are company imposed limits that's absolutely fine and you can't breech them but it's still okay to understand why they are there.