Personnal experience, well a friend of mine who came in for a fall turkey hunt last year. Last week of October and the day time temps were high 70's low 80's. When he arrived he left his truck parked at my house under some trees for 3 days. He left his travel humidor in his truck on the floor, forgot them since he was smoking mine for 3 days and we used my truck. Well on the 4th day we took his also since the hunt that day was going to be about 6 miles of searching. He realized that 4th morning he left his humi in the truck and just got one out and lit it up on the way to the area. It was still dark when we arrived and made our way to the LP. We heard turkeys about 300 yards in the roost at first light and got to within about 125 yards to wait till they flew down to attempt a scatter. Well they remained on roost well after good light (they may have heard or seen us), anyway we were waiting and all of a sudden he started cussing really loud (so much for that hunt). When asked what was wrong he showed me 2 larva's wiggling from the tip of his cigar.
When he got back home the cigars he had in his humi were all good.
I used to just put them aside before and watch them for a couple weeks.
After that I freeze all shipments whenever the ambiant temp is 70 or above.
Overkill, maybe.