Thomson Airways says it's activating contingency plans to switch customers to other aircraft, in the absence of a delivery schedule from Dreamliner manufacturers, Boeing.
The holiday firm is contacting those affected to tell them they will be travelling on Thomson Airways 767 long haul aircraft.
The supplement paid for the 787 Dreamliner flight will be refunded to those customers who proceed with their original holiday bookings, and customers will also have the option to amend their holiday without incurring any amendment fees."
They added: "We understand how frustrating and disappointing this news will be for those customers looking forward to flying on the 787 Dreamliner, we are equally as disappointed that Boeing was not able to confirm a delivery date for us. Unfortunately these circumstances are out of our control."
More top news
A Hampshire-based scientist has taken what may be the first photograph of a Blue Whale spotted in UK waters.
A slice of the Queen and Prince Philip's wedding cake has sold for £500 at auction in Sussex, 68 years after the Royal couple got married
The sun shines on day one of the Great Dorset Steam Fair where 200,000 engine enthusiasts are expected over the next five days.