Posted: 25/06/2017 at 17:21
Advise the neighbours that the RSPB have told you it's an offence to disturb the nest and tell them you have put up CCTV to ensure that nobody does disturb it. It doesn't matter whether you have put a camera up, it may be enough to make them back off.
If you are selling the house and there is an ongoing dispute with neighbours you must inform potential purchasers.
Unless the insurers have provided you with expert opinion, I would demand it before undertaking any work. Are you certain the letter is actually from the insurer and not something the neighbour has created themselves?