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If we are getting precise with names, then really Saxicola rubicola is the current name, not torquata (or torquatus, which is the African stonechat).
As for subspecies, I never see the point in using them in species where the plumage is not discernibly different from other subspecies of the same bird. It makes sense with, for example, Pied (yarrellii) and White (alba) Wagtail, as they are discernibly different, but Stonechats are not. The only reason for calling it ssp. hibernans rather than ssp rubicola is that the books tell us it is that. It is supposed to be darker, but you need a series of museum skins to prove that, probably, and the two intergrade, as well.
My Flickr photos...
Lat/Lng: 56.4, -6.2
OS grid ref: NM4239