Advanced Needs 76 Acid Rain duration?

So I have a game that includes Advanced Needs 76 and have the Acid Rain enabled.

Now it is a bummer, that in the open world enclosed buildings don't keep it out and since it is a rather fresh game, I ran for the Museum of Freedom in Concord, cleaned it out again and slept on the couch there 2x8 hours... and the acid rain is still ongoing...

Anyone has experience with the mod, if it can just last that long or is it a bug?

I had it before, slept for like 10 hours or so in an instance (the wine cellar in sanctuary) and then it was gone.