The main building is to be refurbed at some point this year, including the lobby. Nothing has been posted yet regarding when that starts. We're apprehensive about that ourselves for our stay in May because we ride the monorail often.
As you may be aware, Disney does a good job barricading floor by floor to keep noise and guest inconvenience to a minimum as much as possible. Nevertheless, it was a pain trying to get into the Poly until after its lobby was finished, imo.
So far, it's been the outlying lodges getting done one by one. I think Boca Chica is currently or was most recently, don't recall precisely. Unfortunately, there's no way to know how much your stay may be affected. If we weren't staying in VGF, we'd be rebooking. Much of what we love and want to do at the GF is in the main building.