I'd bet money that the POI would be lower than before. The hotter the weather the more pressure you'll see. The cooler the weather the less pressure you'll see. As a reloader and an NRA highpower shooter, I've loaded shells that when shot during the start of the season, when it was cooler, would be perfect. When the weather started to get hot, like August, those same shells that I loaded were cratering primers and at worst case piercing primers.