Originally Posted by
Nugget_Oz
You should ask for this to be moved to the Skymiles forum but at the moment I believe that BOS-JFK regional jets fly into T2 but there is a shuttle bus (JFK Jitney") that leaves from T2 and takes you to T4 airside without screening. Same ticket will allow you to check through.
On your last question domestic flights fly out of both T2 and T4.
It depends on the flight. I flew a JFK-BOS a few days ago out of T4, it was on an international 757. YMMV.
Anyway, no screening between T2 and T4 anyway, even if you take the bus.