[Personal] HELP

Okay so basically right now my face is not bad but it could be better. I currently wash my face twice a day with CeraVe Renewing SA cleanser and use paula’s choice exfoliant once a day. I am thinking of starting to use Differin Gell to really help clear my face (and stop using those two products like i’ll switch cleansers etc) but the problem is i’m going away in about 40 days and I need to make sure that my face is clear then so if I stay with my current routine it could be ok because its not great but it’s not bad but if I switch and the purge doesn’t finish before then, then i’m gonna be in trouble… what do you guys think I should do? and is there any way to reduce chances and effects of getting the purge.