holy crud MIAMI is going Junior as heck for EMJ FO, having about 40 of 75 guys being hired this year alone!!! With hopes to fill 30 more spots, which looks like it will be via more new hire classes.
That vacancy don't mean is going to be fill with new hires. Actually means that anyone in the ATR can go to MIA EMJ or any other EMJ FO from another base can get a transfer. It can be a guy in a new hire class moving from DFW EMJ (for example) base transfer to MIA or a 1 year ATR guy in SJU (another example) moving to EMJ MIA.
That's how I haven't hold a line yet in ORD, people moves from everywhere and push you down in the list. And as someone comes, others go.