Thanks for fixing this.  For info, there is still an issue with some of the other relations here.  Since at least 4 people are fixing things, I've posted in the Irish forum at https://community.openstreetmap.org/t/coastline-and-relation-breakage-in-killiney-south-of-dublin/128102 suggesting that people work together there.
I mention this not in any expectation of you fixing anything else, just purely for interest :)
