UK holiday carrier Thomson Airways is to use Boeing 767s to operate routes on which it had initially intended to deploy its first Boeing 787s.
The airline says that it is activating "contingency plans" for flights in May and June, in the wake of the continuing grounding of the 787 over battery safety concerns.
Thomson, the first UK customer for the twinjet, says it is swapping to the 767s in absence of a 787 delivery schedule from Boeing.
It had originally planned to use the 787s on long-haul services to destinations including Cancun and Sanford.
Thomson says it "regrets" the substitution, adding: "We understand how frustrating and disappointing this news will be for those customers looking forward to flying on the 787.
"We too are equally as disappointed that Boeing were not able to confirm a delivery date for us but unfortunately these circumstances are out of our control."
Thomson is to refund passengers the supplemental fee they paid to travel on the 787, and will also offer a goodwill payment to premium customers because the space available in the 767 cabin is "not the same" as the 787's.
"No decisions have yet been taken for flights beyond June as we still have not received a delivery date from Boeing," the carrier says, adding that it has additional plans on standby if the disruption extends into July and August.
"Customers travelling on these dates would be switched to alternative aircraft and the same customer policy would be in place," it says. "We will inform customers if necessary, as and when we have a delivery date from Boeing."
Tour operator TUI Travel has 13 787s on order of which eight were initially assigned to Thomson Airways. The aircraft will be fitted with General Electric GEnx engines.
"As a company we are continuing to work closely with Boeing and remain confident in its ability to resolve the issues that have recently arisen with the 787," the carrier states.