Stricken cruise shop the Costa Allegra is expected to arrive in the Seychelles on Thursday morning.
The vessel, which is operated by the same company involved in the Costa Concordia tragedy, was cast adrift in the Indian Ocean after the blaze broke out in an electric generator room on Monday.
The stranded travellers - who include 31 Britons - were earlier being towed to Desroches, a small, coral-lined island in the Seychelles, and were due to reach it by this morning.
However Costa Cruises later announced they could not disembark there as it was not safe enough and the ship would instead be taken to the main Seychelles island of Mahe, where it is expected to dock tomorrow morning local time.
The change of plan was disclosed after guests had been asked to prepare their luggage so as to be ready for the earlier time of disembarkation.
The company said in a statement: "Costa Cruises informs that in view of extensive and accurate checks carried out with local maritime experts' support, in order to ensure the safety of our guests on board, the disembarkation on Desroches island cannot be performed and therefore it has been decided that the ship will be towed to Mahe/Seychelles.
"The disembarkation in Desroches does not assure the necessary and adequate security conditions for mooring the ship and guests' disembarkation.
"In addition, logistics and hotels on the island are not enough."
Costa Cruises said helicopters would ensure the continuous supply of food, comfort items and flashlights to "mitigate guests' discomfort given the difficult conditions on board".
It added: "Costa Cruises is working with all the authorities responsible for the co-ordination of the emergency to ensure the best possible assistance to all our guests and make their discomfort as short as possible and to reach their next destination.
"The company is sincerely sorry for the inconvenience. Absolute priority is to make it as short as possible."
The ship was being towed by the French ocean fishing vessel Travignon and two tugs after its engines, lights and air conditioning were left with no power.
The incident came after the Costa Concordia cruise liner, also operated by Costa Cruises, struck rocks off the west coast of Italy on January 13, leaving a death toll expected to reach 32.
Among the Britons on board the Costa Allegra was a woman whose brother survived the capsizing of its sister ship.
The siblings' mother, Jayne Thomas, from Sutton Coldfield, had yesterday had no news from her daughter Rebecca, who was working on the Costa Allegra as a dancer.
However although her 19-year-old son James was still recovering from the mental trauma he sustained when the ill-fated Concordia ran aground in the Mediterranean, she said she did not feel any ill will towards Costa Cruises.
"I have no feelings towards the company," she told the BBC. "I think it's just a twist of fate that they've both been involved in two such unfortunate incidents."
Some 636 passengers and 413 crew members were on board the Costa Allegra when the fire broke out but none were injured.
Photos showed hundreds of people milling about on the ship's outside decks and officials said passengers would sleep there as well, instead of in their unlit cabins.
The Allegra, whose Italian name means "merry" or "happy", left northern Madagascar on Saturday and was cruising towards Port Victoria when the fire took hold.
Italian coastguard officials said emergency generators were keeping the ship's control room illuminated and communications equipment such as radios running.
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