If you go to NYC, expect to take a lot of AA jumpseats. The good news is there are lots of them and few AA jumpseaters between DFW and NYC. Your seniority will go a lot further in NYC, too. ATL is very senior.
Try to plan on moving asap. You don't want to use the call in honest policy ever while you are on probation. Termination would be a real possibility. You don't want to use it if you can avoid it once you are off of probation, either.