Both Aurigny and Loganair want to fly the Guernsey to Jersey and Guernsey to Southampton routes.
Scottish region airline Loganair and Guernsey's state-owned airline Aurigny have been operating flights between Guernsey and Jersey since the loss of Blue Islands on 14 November.
Loganair initially also put tickets on sale for the Guernsey-Southampton route; however, it withdrew them after realising it was a designated lifeline route, meaning a States-issued licence was needed.
On 17 November, Guernsey's Economic Development Committee decided the inter-island air link should also be classified as 'essential' - and this would take effect from mid-January.
Guernsey's Transport Licensing Authority (TLA) says it has since received three licence applications.
People have until Friday (5 December) to comment on Loganair's application to operate passenger and cargo services between Guernsey and Southampton, and Aurigny's application to operate passenger and cargo services between Guernsey and Jersey.
Loganair has submitted a second application to fly passengers and cargo between Guernsey and Jersey, which the public has until 15 December to comment on due to a later submission.
Islanders can send letters or emails to the TLA to comment.
TLA President, Deputy John Gollop, explains why they are requesting input:
“Recent weeks have seen a lot of change in the landscape of Guernsey’s air travel market, representing a material shift and significant change for the travelling public.
"It is important therefore that they have the opportunity to provide feedback on the applications.
"We hope to hear from as many people as possible.”
Ultimately, the TLA will determine applications against criteria set out Guernsey's Economic Development's air licensing policy and the TLA legislation.
Current essential routes include Gatwick, Alderney and Southampton, with Jersey added from 15 January.

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