the ravellers were released from quarantine hotels after the government removed the red list.
The PA news agency understands they were told they could leave as of 4 p.m., around 12 hours after the requirement to self-isolate in a hotel was dropped for new arrivals.
It has been reported that some travelers left their accommodation before this date.
Only those who tested negative for a coronavirus test were allowed to leave.
Health Secretary Sajid Javid said released travelers “will get a refund for the part of the space they have booked and have not used”.
People with a positive result, or those who are not fully vaccinated and are a contact with someone with a positive result, should remain in quarantine.
Concerns over the Omicron variant of the coronavirus led 11 African countries such as South Africa, Nigeria and Zambia to be placed on the red list.
People arriving in the UK from these locations were required to spend 11 nights in a quarantine hotel at a cost of £ 2,285 for solo travelers.
But Mr Javid announced on Tuesday that the list would be removed because the prevalence of the strain in the UK meant it was “now less effective at slowing Omicron’s foray from overseas”.
Jonathan Mogford, who is responsible for the quarantine service managed at the British Health Security Agency (UKHSA), told the Commons Transport Committee on Wednesday that there had been “unprecedented rates” of positive cases of Covid among red list travelers.
He said the latest figures suggest that “almost 5% of people in hotels are positive.”
There have been “around 5,000 guests in this series of red lists,” he said.
His comments indicate that around 250 of those people have tested positive.
UKHSA chief executive Dr Jenny Harries said travel restrictions had “a time and place” to protect public health.
She told MPs the Red List was deployed “as a delaying tactic”, giving the UK “time to prepare” for the Omicron variant.
But now that the strain’s growth rate in the UK is “important” it is “really important” that the country-specific restrictions be lifted, Dr Harries said.
Travelers entering the UK must take a pre-departure test and self-isolate until they receive a negative result from a post-arrival test.
Committee members and former Labor Minister Ben Bradshaw said Transport Secretary Grant Shapps told him the travel test regime was “unnecessary”.
He said: “The Minister of Health told me in the House yesterday that he thought they were unnecessary and the Secretary of Transport told me last night in the hall of the division that he thought they were unnecessary. they were also unnecessary.
“Someone is obviously holding them in place, who is holding them in place?” “
Dr Harries replied, “It is not for us to make decisions. We provide advice to ministers, and I cannot speak for any of the ministers you just mentioned.
Downing Street insisted the measures were not “unnecessary”.
The testing requirements “remain important to help prevent seeding of additional Omicron in the UK,” the Prime Minister’s official spokesperson said.