Long Straddle Play?

GIL reports next Thursday, 8/13. IV has leveled off but is still at a premium to HV with more of a bias to the put side. Looking at earnings for the last year shows serious down gaps morning of every report. A quick run through the risk graph shows our breakevens next Thursday at $15.30 and $19.60, roughly, but that's based on today's option premiums, stock price and IV. Is it possible that GIL will gap that far? Absolutely, especially based on the last five earnings reports(Not much of a sample though). Nothing is certain, however, so I would wait until day before earnings to enter the trade-no reason to pay for time you don't need. If anyone could tell me how to guesstimate what the premiums will be next Wednesday that would help. Too many variables to come up with anything more than a guess though, I presume.