About 70 UK nationals who have spent 16 days in quarantine on the ship in the port of Yokohama had expected to fly home on Friday.
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They are expected to land at an RAF base in Wiltshire before being quarantined at Arrowe Park Hospital in Wirral.
More than 620 people on board Diamond Princess tested positive for the virus.
Two Japanese passengers – both in their 80s and with underlying health conditions – were confirmed to have died after contracting the virus on board the ship.
The Princess Cruises vessel was carrying 3,700 passengers and crew, including 78 Britons, when it was quarantined in Yokohama on February 3, after a man who disembarked in Hong Kong was found to have the virus.
At least four Britons also contracted the virus on board, but those due to fly back to the UK have tested negative.
Japanese health authorities allowed passengers who had tested negative for the virus to disembark at the end of the ship’s 14-day quarantine period.
Princess Cruises confirmed that about 600 passengers were the first to be cleared by the Japanese Ministry of Health and released to disembark the ship.
Several hundred others were expected to be cleared on Thursday by health officials.