By the tyime you are done with Indoc, Systems, Sim, and OE, you will likely have been through a couple if not more vancanciy announcements, and you will most likely be able to hold LGA on RSV right off. Remember, on OE, you can tell the company you want to do that out of any of the 4 bases, and they will try to do that for you regardless of your expected domicile at that time, so even if you are still waiting to get into LGA while on OE, you can do OE from there and likley get another Vacancy Announcement to move to LGA.

By the time my NH class and the one after me was done with Sim, 100% had their top choice and that was before any of us started OE, and people went to all 4 bases.