The authorities are going to come down on this one like the proverbial ton of bricks.
I used to live in a grade 2 listed world heritage area (with windows very like yours!). Our new NDN put up a bloody great satellite dish on the outside of his house - he was commanded to take it down within 24 hours of it being installed.
Your situation is much worse, I can see that, but stand firm and take deep breaths. This one will get sorted. 