I think many people misunderstand how these PROFESSIONAL breeders operate. They produce bees bred to the CLIENTS needs, not to their local climate.
The GOOD ones are purely exploiting their early seasons compared to here where it is a far more hit or miss affair (and yes, we run 1000 mating boxes and produce a LOT of home raised queens but ride both horses.)
If a gentleman in, say Cyprus, produced queens which were perfect for Cyprus he would not sell many to the north. Yet he does. Why? He is not breeding stock designed for Cyprus, nor ultimately sourced and selected from there. It is northern adapted and just southern raised.
Ditto our friends in Piemonte. They drone flood their area, they select breeder queens from as far north as Finland (in fact one of them was there in the last two weeks). They trial them and then reselect again, and then graft and mate them in the areas dominated by their sought after drones. It ain't perfect but the idea that you are buying bees adapted to a southern climate if you buy from a southern source is just not accurate.