Considering the numbers involved in terms of the planned recruitment (60+) i would say its both possible and very unlikely at the same time. On day one you pick a number out of a hat for your seniority number. Depending on when you start and what number you pick you may be at the top end or the bottom end of that scale. Either way it will still end you up on a part time contract for 5 years at the moment with the training costs being paid for by yourself (both type rated and non rated in their own respect). Also it has happened in recent times that a clause is used to type freeze new joiners for 3 years so if you join on the 737 it could well be that you are frozen to that type for 3 years before you are eligible for another type through the pilot bid. The only fleet at present where part time does not exist is the 787 which, at the moment, would trigger your full time contract but that would be years down the line for new joiners who join within the next year.