If you go to the awards page for AA on EF, there is a radio button with a ? in it by the A class. When you hover over the ?, EF displays the text,
First - Upgrade using miles/SWU or restricted purchase of First class on 3-cabin flights only. Note my bolding. That is what is leading to my confusion. I called again today, no A class for RTW, but EF does show availability.