Is it the right time for me to start PMM?

Hello Everyone! I'm thinking seriously about starting PMM this week, once I've finished WBB. Normally, I would wait, I think, as I would like a few more rounds of the WBB work before starting. BUT! I'm back in grad school full time in September, and the time I have to dedicate to my magic is going to have to be reduced quite a bit. If I do PMM and the rest of AWP at the same time, I'll be done by the time my classes start back up. The workload is huge, and I also read on the last hand out that it's supposed to be repeated until your prosperity is running on auto-pilot. I think I would only be able to accomplish one round - and I'd like to do it before graduating as I would like to prosper right out of school! Any advice appreciated! I suppose I'm leaning towards waiting...but I'm very torn.