It looks like https://www.openstreetmap.org/way/1376867539/history was accidentally created as a duplicate way of https://www.openstreetmap.org/way/366119186 in this changeset and as well as fixing some invalid relation that created others ("5446375 | Miltonsfields" fell out of the database last night).
I've deleted the duplicate and re-added the missing relations to https://www.openstreetmap.org/way/366119186 .  The relations I've edited in https://www.openstreetmap.org/changeset/164846491 , https://www.openstreetmap.org/changeset/164847085 and https://www.openstreetmap.org/changeset/164847214 now verify in JOSM as valid polygons, so hopefully all is geometrically OK now.