717 and 320 training honked on the brakes over the summer and fall. Several factors drove this. Throughput of those training lines kicked in again recently, but these jets are way understaffed. That's why the ginormous numbers in the 320.

I wouldn't be the least bit surprised to see tons of 88 and 717 guys bid to the 320 and 737 leaving some, but few, for new hires. The 7ER had a flood of new hires assigned last winter through summer. The trailing edge of that "rat in the snake" is finally now on the line, so they are well manned...and it is now a shrinking category (the A330 is in some cases junior to the 7ER now...and the 330 is a growing category). Due to rapid growth, most guys who can move will go to growing categories and benefit from the relative movement created by the airframe growth and pilot retirement expected in the next 2 years while on their next seat lock. Food for thought.

By contract, vacancies have to be offered via AE and unfilled vacancies go to new hires. Last spring summer was weird because the early 14 hires were still in seat lock, many '10 hires wanted to remain in category but move to their base of preference and the reversal of 7ER retirements. I don't see funky dynamics this year...I see pretty massive growth (and thus relative seniority opportunities) in the 73 and 320. I think new guys should expect 88s and 717s...some will be surprised to get other opportunities mostly in NYC.