Sabre and Travelport users will temporarily be unable to book United Airlines' Economy Plus seats while the airline switches to a new reservations system.
According to Sabre, the suspension begins March 3, and there is no set date for restoration.
"We are working closely with United to return Economy Plus seats to the Sabre GDS as quickly as possible," Sabre said in a statement. "There will be no impact to Economy Plus seats booked through Sabre prior to March 3."
Sabre said a temporary suspension was necessary because the solution Sabre built four years ago to allow the sale of premium seats was specifically designed to work with United's current reservations system.
"Once they switch a new system, technology adjustments will need to be made by both of us to get their product back in the GDS," said a Sabre spokeswoman.
Amadeus has an agreement with United to make Economy Plus bookings available to customers by mid-2012.
Amadeus said it has received no indication that the timeframe will change.
Correction: United's res system switch will affect Travelport customers, too, as Apollo and Worldspan users currently can book Economy Plus seats, Travelport said.
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