I'm still new at cake baking/frosting, so I haven't got all the kinks worked out.
The last time I made IMBC the texture was lovely and smooth when it was first made. But by the time I crumb-coated my cake, let it chill, applied the final coat of BC, and let it chill again before piping a border, the buttercream was starting to get very soft and a bit "spongy." Would beating it again help to restore the smooth texture? I don't think chilling it would be the answer, because I'd have to let it return to room temp again before beating it.