Where I live we have a spring flow, and then no nectar during the hot summer months. The Carolinian quit laying after the flow is over, and the numbers of bees decrease. Will this cause a problem with SHB if there isn't enough bees to protect the hive. I have beetles in everyone of my hives, but my bees attack those them if they come out on the frames.
I keep carnis in East Tn and had no major SHB problems during the late summer. One hive last year had had 8 supers on it before harvest and had beetles in the top super in June. But once I pull the supers they controlled the hive throughout the rest of the year.
So far this year it's been a down year for beetles.