So if you do match at a 2-4 then you need to do something during yr 1. Your 2-4 program wont help much with this. That being said the prelim/TY programs that would be left might be less desireable. Residents have told me that when you put together your ROL if you are doing a 2-4 then they do a secondary match. So if my 1st choice is a 1-3 and I match then obviously I am set. If I dont and I match at my # 2 which is a 2-4 then my prelim/TY ROL would go into effect. Additionally, If my top 2 are 2-4 progs I CAN submit separate TY/Prelim ROL based on where I match. So lets say i want to be in the same city all 4 yrs..
I rank Cook County #1 then I put 4 TY progs after that on my secondary list
then I rank UAB # 2 I can put all the TYs in Birmingham there, or if I want to live in NYC for 1 yr then I can put them on that list.
I know this is a long answer but hopefully it answers your Q.
Arthur