In addressing the question of whether to treat package bees before placing them in their new hive. We should remember that package bees, essentially 'shook' from other hives, typically harbor minimal mite populations, even without prior treatment. A Nuc may be different but as we said there is a high likelihood of a host of problems with Nucs.
Your package bees should be given the chance to settle in and start building comb and even producing brood. Introducing treatment prematurely could disrupt the hive's establishment process. Even sugaring will cause the bees to do very little for 24 hours while they groom themselves. So I would encourage everyone to just feed the 1 to 1 mix of sugar and water and allow the bees to settle in and do their thing. Let’s give them a solid 4-5 weeks before we conduct a mite check. We really need to pay attention near the end of the nectar flow which could be very early this year if the dry weather continues.