Getting toward "clear-as-mud" realms here, at least for me -- in Wales at any rate, there would appear to be for sure more than one contender as to which St. Hilary, a church of that dedication is actually dedicated to. "Llanilar" is (Mid-anyway) Welsh for St. Hilary -- but there is seeming uncertainty as to whether that refers to the best-known saint of that name, the 4th-century Hilary of Poitiers; or the basically very-little-known, but possibly Welsh, saint and martyr St. Ilar; or even a different bod again, the definitely Welsh St. Ilian -- and it would appear that St. Cybi may also get in on this thoroughly confused act. There is, very far south in Wales -- in Vale of Glamorgan, just south-east of Cowbridge -- another village named after, with church dedicated to, St. Hilary. In this mostly Anglophone part of Wales, this settlement's official and generally-used name is St. Hilary (Welsh version "Sain Hilari" -- thus differing from usage for Ceredigion settlement as above). We learn that nowadays at any rate, the Church's ruling is that the saint concerned here, is "him of Poitiers", and that's that -- apparently re the Ceredigion settlement, they're not so sure.