You can pick your sim partner to a certain extent. In my class we had a couple transitions from the Saab and 5 upgrades. The instructors don't want company employees paired together if possible. That way new hires get someone a little more experienced to work with. The best option would be to pair up with a captain upgrade for 2 reasons. 1) you don't have to switch seats after 2hrs to perform PF and PNF duties. 2) The upgrades' seniority number will be higher therefore you can choose a more suitable sim time. Sim schedules is also based on seniority.
There will probably not be as many upgrades as there are new hires since classes are relitavely full with around 35 every 2 weeks.
10 sim sessions minimum. 1 - FTD intro, play day if you will, 2 - 2engine ILS, 2 - 2engine nonprecision, 2 - 1engine ILS and nonprecision, 1- specialty day (windshear, gpws, cfit, etc), 1 - phase check, 1 - check ride.
If remedial is needed, your checkride is pushed back a day or whatever.