According to the hiring folks at AA (and United), the AA WO pilots make up one of the smallest percentages of application groups as compared to other regional airlines. Not sure why AA WO regional pilots are so opposed to just putting their apps in elsewhere, but they don't seem to want to do it.

Everyone should have an app in once they hit about 750 hours with their regional, and update regularly as they upgrade and start accumulating TPIC time. Update it every 2 weeks.