They have left themselves open if they have got rid of all UK staff and kept French on. There could be an unlimited pay-out at a tribunal due to discrimination, rather than the 1 year's salary they have built into their worst case model.
I know it is not a simple as that, but they have given away a few aces to the employees, got them selves in an undefendable position, and will probably pay out a fortune at arbitration.
The French are all employed shoreside on the French side and will be under different contracts. There are a handful of French seafarers still on the ships left over from the merger with Stena line many years ago but it's minimal and again they're on different contracts.
