Given the fact that Iran's air defenses are a joke against Israel's air dominance. Their only chance would be to spam Shahed drones throughout the entire day instead of trying to sync them with their nightly ballistic missile strikes. By sending Shaheds during the day it forces Israeli planes (that need to fly 1,500km to bomb Iran) to swap bombs for A2A missiles. Every missile hardpoint = one less bomb. Jets can refuel mid-air but can't rearm, so any F-16/F-15/F-35 stuck swatting drones aren't dropping bombs on Iran. Once missiles are gone, they have to RTB to Israel to reload.