Anyway, back to the point. No problem in using younger pigs for bacon/hams - as the others say, just expect everything to be smaller (and maybe leaner, depending on how you feed).
I sent some pigs off last spring a bit early (4 mths) because I needed the space and had customers waiting for pork. The chops were half the size of my usual ones, but they were hugely popular with people who thought they were brilliant for barbecues. Also, the quality of the meat was amazing - incredibly tender. I also did bacon from the bellies - fantastic.
All you need to do is advise the owner of your concerns about size etc - the decision is up to him/her. Good luck. Liz