BLT is supposed to be a "soft" goods refurb, meaning painting the room and repairing or replacing items such as furniture as needed and putting in new carpeting. It typically does not involve very loud noises like you can get with a complete redo of the rooms such as BWV just had and BCV is currently getting. A typical process followed and likely to be followed at BLT is that they will start with the top floor and then work down floor by floor, doing each floor in sections, possibly three at BLT -- one for each wing and one for the rooms in the center between the elevators. It is usually not an issue for persons staying at the resort except for those in a room that is directly below or above the area being worked on, which can sometimes hear some noise.
Any particular section done during a "soft" goods refurb can be done fairly quickly, but the whole process, since they are only doing a little at any one time, can last a long time, and I would suspect the one at BLT, which started recently, could run into late this year or early next year.