You can ignore the live departure board, it is total fiction. The taxi drivers have been taking loads of passengers to Dover Priory and then taking them home again as there have been none of the trains running as shown.
My family have just been down to catch the 1245 as shown on the live departures board only to be told nothing is running. When my sister-in-law queried this she was told that the live departures board had nothing to do with them! So much for the marvels of integration on the privatised railway. Nothing ran at all yesterday because the privatised rail operators would not have made money for their shareholders and have no requirement to offer a public service.
My family are now in a taxi to Ashford to catch the high speed from there.