You cannot assume that the closing of the boardwalk view rooms from Sep to Nov 2023 indicates the time when the internal boardwalk view rooms will be refurbished or when the refurb of BWV will actually begin (more likely much earlier in 2023). Likely, that two-month closure is more related to some outside work that is planned. Moreover, if one assumes they will be doing a refurb of all the internal boardwalk rooms at once during that two month period, that would also require the closure of the large number of pool/garden view rooms that are across the hall from the boardwalk view rooms to be out of service, because they need to close the hallways when refurbing the rooms on either side to allow for the workers carts, inlcludng carts taking away things removed and supplying replacement items.
In the past a typical BWV refurb took close to a year, and as far as internal room refurbs were done, they worked on half a floor at a time, starting with the 5th floor, while leaving all other rooms open. They finished and reopened the half, moved on to the other half of the floor, and, when done, moved down to the next floor following the same process.