A few days ago a coordinating council for the nomination of Kamianets-Podilskyi to the World Heritage List was formed and held a meeting (source). Interestingly, they only discussed the natural features of the canyon, and noted that discussions regarding the cultural component would fall "within the framework of other specialized programmes" when the creation of the nomination file itself willl take place (which will be the final step of a long programme that aims to primarily ensure the proper preservation and upkeep of the canyon). Anyway, the idea of nominating the Smotrych Canyon only for its natural significance has been brought up before, so I'm not surprised that they're going for a mixed nomination now, but not sure how successful this attempt will be given that all previous ones did not achieve much.