Bats hate owls and vise versa. I would plug up the hole but make very sure that no one is inside, like with babies or something. Just a bad night and decided to stay in thing.
Then set a dummy owl, from a sporting goods store, on the ledge or area that they enter. This is the gate keeper and should drive the critters away for good.
I would send a volunteer in the attic to check for bat guanna. This needs to be out of there. Carries diseases and not good for the homestead.
I would imagine that because of a bat's social dependency, you have way more than a couple of visitors.
Good luck and don't let this drive you BATTY!!!!!
© 2016 Renovate Your World LLC