I manage the Beach & Yacht Club FAQ thread. We try to keep the first post in that thread updated with the most current refurbishment news. So far we know the work will be started in 2016, I believe in January from what we have heard. The rooms will undergo a hard refurb with replacement of furniture and décor. I believe the studio villas will be receiving some sort of pull down bedding to sleep an additional guest. There should be some info on the proposed changes on the DVC sub-forum. I'm guessing the hallways will be refurbished as well. Not sure about the public areas on the first floor- some work was already done there recently.
I don't think there are plans to build additional villas, so it is not construction work like other resorts have experienced.
We really don't know the timetable at this point- how long the work is scheduled to take or how far along they will be in April.
According to guests who have stayed at Disney resorts during refurbishment work (which happens all the time), Disney does their best to minimize disruption to guests who are there during the refurb period.
We have heard mixed reviews about the current condition of the villas on the thread. I'm not sure anyone has reported back on the thread that conditions are unacceptable, but there have been some reports of wear and tear, some dings and scratches and outdated décor.
Hope this helps.

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