Guernsey will keep its mail plane service, while Jersey risks having its deliveries downgraded to a ferry.
The Royal Mail is consulting with the Crown Dependencies on the service it provides in future, due to falling volumes and cost.
That may mean services to the Isle of Man and Jersey swap to a ferry, and with that Jersey will lose its next day, first class deliveries. That could happen later this summer.
But the chief executive of Guernsey Post, Boley Smillie, says he has a guarantee that an aircraft will keep serving the island, both for incoming and outgoing mail, due to the needs of the card companies, part of the fulfillment industry, which relies on a fast dispatch:
"Their whole business model is based on next day delivery, which you can only do through the use of the aircraft."
He says the Royal Mail also benefits from business from Moonpig and Funky Pigeon:
"They're effectively customers that we share with Royal Mail. All of the volume that we process and handle goes to Royal Mail. They're important, and for that reason, the aircraft will remain while we have those businesses."
He says they're 'in constant dialogue' with Royal Mail over service provision:
"Royal Mail have acknowledged we need to keep that aircraft for as long as that fulfillment industry exists here."
He says despite the card company mail being outbound only, not using an aircraft for incoming mail would mean it is flying what's known as a 'dead leg' which is why first class mail posted from Britain should arrive the next day, although he admits strike action in the UK has made that less reliable lately:
"We're delivering product in Guernsey the day we receive it. There are much publicised delays in the UK. It's something that Ofcom are investigating. We know Royal Mail have had challenges with industrial action and employee relations.
If customers are experiencing unacceptable delays, then they should contact our customer service team and we'll do our best to try to get to the bottom of what's going on."