1. The roads are kept because the ingress and egress will be the same. I don't know if the bus terminal will be changed to sawtooth layout, but parallel stands seem likely for this small size of intermediate stops. 
2. The `addr:housenumber=` should be kept as they still exist, and would be reused somehow 
3. It's usually not a good idea to draw the exact layout of the construction site in the status you find now, as OSM is not about recording construction progress. There will only be one continuous site with 2 towers, the Low Block extending from Kwun Tong Rd to Fuk Ning Rd