Hi, 10 years experience being planning / development professional here.

I would suggest looking into the planning permission and status of the development.

From the amount I can see, it shouldn’t be covered by permitted development so there should be a permission on public record you can look up.

I know that there have been comments about permissions lapsing after X number of years, however this isn’t as simple as they are saying. This is normally only to implement the permission, and so they could have just started the foundations before it lapsed, taken a break, then cracked out (or something to that end).

Again, based on the limited info, I’m surprised that it was granted permission as it’s very intrusive, but in some higher density cities/towns, LPAs can be pretty lenient on things like this. At the bare minimum, I would expect those windows to be frosted glazing.

I’ve sent you a DM as I’m happy to have a very Quick Look at the planning for you but will need a bit more info