The very reason they went into bargaining with the pilots earlier than predicted is because their fleet obligation did not meet their fleet obligations.

There are a few outcomes here:

1: New contract with very little changes for the pilots and a new order of 787s just like the last AC pilot contract. (Unlikely since the WestJet and Jazz pilots are paid more in their first 4 yrs of employment compared to AC).
2: New contract with massive pay bumps and negligible fleet changes (a few A220s or more lease pickups of A320CEOs/A330s/787s)
3: New contract with a pay bump that's not nearly enough for a flag carrier and a few other concessions from the pilot group in exchange for a large aircraft order (a lot more 787s or perhaps the A350 which they've been continually kicking tires on).

As someone who's got a lot of info on where things are headed, I'd bet on option 2. They have to pay to get bodies in cockpits and the training department. WestJet had to cancel new hire classes and now that they are the highest paying carrier in Canada for First Officers, they are doing 40 new hires a month and are able to meet training obligations in a timely manner.

AC will want to avoid a strike in exchange for mass growth. Getting a few tails here and there will still work.