ahha wow..dude im in your same situation this is insane....except mine is a 1 year mistake and im pretty sure its going to ruin me. You are only 2 months tahts not bad at all i WISH mine was 2 months, not one year. Once you submit you cant change, thats what amcas said when i called them so im just ****ed. You could call amcas but i think they would tell you the same. honestly though its 2 months thats nothing, id just leave it be. Or you could update schools...im just going to send schools an update that i made the mistake and hope i havnt ruined 4 years of work over a 1 digit typo. I almost feel just like not wasting time on secondaries after my mistake.
If amcas wont fix yours, then i say just leave it and dont even worry like i said 2 months is absolutely nothing...if it makes you feel better you can laugh at how stupid i am for a one year mistake-_-. Oh you could also send an update on the secondary or through email to each school you are applying to, just ask them which they would like. But for 2 months, its not even worth the trouble imo. I mean lets say you worked for 18 months, but your mistake results in it seeming like you worked for 16 months, no one is going to even know the difference at all.