Interesting observation is the number of 2016 hires got emails from crew planning that they were getting close to upgrade and to double check their vacancies. Most junior I heard of was May 2016 LAX FO. The others were Feb 2016 OAKs.

I'm not sure what the threshold is for those to go out and how they have their vacancies set up, but I'm guessing they are bidding for first available in those bases and are opted-in to the lance program