It's hoped to get a new franchisee in place for Alderney Week, which begins on 7 August.
Guernsey Ports says it was given little notice of the intended closure of the Aviator Cafe, which stopped operating last night (31).
Alderney Week, which is the busiest travel time of the year for the island, will see people arriving in number from Saturday 5 August.
Ports says several businesses have said they're interested in running the cafe short term, until the end of the year.
These will be treated as formal expressions of interest.
It's planned to get an operator in place within days. In the meantime, passengers are being reassured that while there won't be a full food and drinks service, there is a fresh drinking water dispenser in the terminal.
Next year, work is planned to go ahead on rebuilding the terminal and a new, longer runway.

Guernsey gives £75k for Islands Unlimited inter-islands sailings
Guernsey tax package to raise more States income but protect low earners
Changes to make Guernsey's buses more reliable
Aurigny plane makes emergency landing after leaving Guernsey
New festival part of Guernsey's Seafront Sunday
Guernsey firefighters tackle round-island walk in full kit
No provider awarded subsidy for seasonal inter-island ferry service
Guernsey's key industry 'stable' in a turbulent world