In my opinion the SC has done the correct thing, though I am sure that some may disagree. The fact that the cats have been at the scheme for several years, albeit without approval but possibly with knowledge of the SC could indicate “tacit acquiescence” on the part of the SC. It would be unreasonable to request the removal of the cats after this length of time.
Pet owners generally fight hard to keep their pets and the SC decision may have been an attempt to avoid fighting a time consuming losing battle.