I agree that it probably won't make a difference in re. A. However, I did give written notice- not to get him to comply, which I knew he wouldn't. And he didn't. I did it to have a written record because I might have to get a protection order. (different situation- never married, no kids, felony level misconduct by X.)
William Eddy's book "Splitting" gives good advice on case management with a high-conflict person. My tendency is to think in terms of proof rather than having any impact on the A.