I have an antminer S2 on a pool. Will it need new software to deal with bigger blocks? Sorry if its a dumb question but as they say the only dumb question is the one that isnt asked 
Ill ask anyhow.
No. The pool takes care of assembling the header, which is what your hardware tends to work on. While the exact content of the header changes, the characteristics stay the same. Your mining hardware will be fine Ill ask anyhow.