Condor is likely to operate a 'much reduced timetable' to France for a 'significant part of 2021'.
The boss of the ferry firm has reconfirmed its intention to resume fast ferry sailings on 21 May.
In an email to customers, Paul Luxon says it will be 'fantastic to be sailing again'.
But he says 'question marks' remain over the French route because of the country's third lockdown and comparatively low vaccine rates.
It means the ferry firm is likely to have to run a 'much reduced timetable and frequency of service in and out of France for a significant part of 2021'.
The update to passengers it is promising that Jersey and Guernsey are starting to relax their restrictions and that there has been an increase in booking interest.
"..we hope the Islands make the most of the flourishing staycation market in the UK and show British holidaymakers what they have been missing."
Condor Voyager will be joining the fleet this summer.


Guernsey's former Chief Minister admits making indecent images of children
Guernsey Deputy and wife arrested and questioned by police
Guernsey Post expect to deliver 750,000 parcels this Christmas
Alderney to get a Royal Visit on 15 December
Two airlines bid to operate Guernsey's essential air links
Guernsey overtakes Jersey as top Channel Island for UK Sea Travel
Agency staff to cover ambulance services in Alderney over Christmas
Guernsey venues highlight support training with window stickers