Well the mason bees I set free have been hanging around the yard. They're so timid and curious. I swear one even recognized me. It flew around me in a curious manner. I'm still not sure releasing them was the right thing to do now that I know they're an invasive species. We have an awful lot of mason bee species in the US and they're so friendly too. The only way I could see one of them becoming invasive is if they hatched out earlier than all the rest to get prime hole reinstate for a nest. Perhaps parasitic wasps and sawflies don't use them as hosts or are somehow overlooked by woodpeckers which would eat the natives. I haven't found a clear answer yet.
Whatever the case they're bees and thus beneficial pollinators. As I said they're hanging around the house and even with their small size they're easy to spot. They mostly hang around the nesting holes, undoubtedly waiting for females to arrive. The brilliant thing about all mason bees though is they're not bias against certain nectar sources, they just go for the nearest flower source. I'm happy to see in this case one of those sources was the bloodroot I planted.