Looks like loarie had asked them to confirm (and indeed their proposed subspecies would be well out of range at that location and can’t be reliably ID’d visually). I’ve commented with some more details.
See also this observation: https://www.inaturalist.org/observations/2559987
While range is regularly used for identifying bird species (e.g. American vs. European Herring Gulls) it has risks and is more often avoided for subspecies. Subspecies are also just controversial in general… there have been many discussions about this subject on the forum.