Hi Jon - thanks for coming back to me. I had thought OSM was telling me you had directly edited the relation, but with some more digging I can see I misunderstood - the relation simply changed as a by product of the ways you were editing. I will see if I can work out how to properly delete the relation! Thanks, Mark

This relation now has no descriptive tags. As such, iD won't let me edit any of the constituent ways without fixing this - but as I don't know what it's supposed to be, it's tricky!