If you say on your AMCAS app that you are taking the August MCAT, they will wait for those scores before reviewing your application. It will delay your application process considerably, but it is not the kiss-of-death that some would have you believe. I took the August MCAT last year (was happy to get a 30 on it!) without having taken the April exam. From the fact that you would consider re-taking with a 30, 31 or 32 I must infer that you are only interested in really top schools, and I'm not really sure about the screening process for all those schools. I did receive secondary invitations from some top ranked schools and was admitted to one that did not have a secondary (also 4 other admissions, and 5 waitlists to lower ranked schools). I would strongly advise you not to concentrate your applications on only top-ranked schools. There is considerable randomness and unpredictability in the whole process.
But none is right, there is really no reason to re-take with a score betwen 29 and 32.