Even the Manchester-Manston service could be economically sustainable if seen in combination with traffic to Belgian coast and Bruges-Ypres/Flanders,etc...Grtz
The Cityjet MAN-ANR route serving Flanders seems a miracle survival: I have flown it many times when I've paid £100 return with about twenty passengers, but rarely one or two others £200 or so when it's been full. Once when I quoted a fare of £250 my employers kindly advised me to use the Eurostar instead - I suppose there had been a block-booking. And this is always Fri out, Sun back. I know yields are all but it seems precarious, especially after the MAN-Rotterdam route was dropped.
Let alone the competition from the
non-stop SN/Flybe rotations each day MAN - BRU. I think MAN-Manston- Oostende is a non-starter, especially with the efficiency of Belgian railways