Migrant rights groups have warned that British residents could still be barred from returning from abroad because of the switch to digital visas, despite the government extending the deadline by three months.

The Home Office announced last week that the transition to eVisas as the accepted proof of British residency rights would begin at the end of March 2025, ditching the original 31 December deadline with just weeks to go after the transition was dogged by technical problems.

While the delay has been mostly welcomed, there are widespread concerns that the change in schedule will not reach overseas airport staff and border officials in time, with British residents potentially refused permission to travel and left stranded abroad as a result.

“Based on our previous experience, we are emphatic that this message will not filter down to every carrier, every check-in staff member and third party, and every boarding gate staff member,” the Immigration Law Practitioners’ Association (ILPA) and EU citizens’ rights group the3million said in a letter to the Home Office after the delay was announced.

Under government rules, if a transport operator carries a passenger to Britain who is then not allowed to enter the country, the operator must cover the cost of taking them back. “Carriers, being commercial organisations, are risk averse,” the letter said. “Therefore, unless they have received confirmation from UK authorities that someone has permission to travel, they will very likely err on the side of caution and deny that person boarding.”

“We are concerned these measures are kicking the can down the road and will not be enough to avoid travel chaos,” Monique Hawkins, policy and research officer with the3million, told the Observer. “We need reassurances that no one who gets stuck abroad through no fault of their own will have to carry the financial, emotional and disruptive burden of it. It cannot be left to individual people to convince airlines to let them travel on expired documents, the responsibility needs to firmly sit with the government.”

The eVisa system has already been introduced for EU citizens in the UK. “We’ve seen how technical errors push people into losing job opportunities and tenancies, being refused access to services and having difficulties travelling,” said Hawkins. “It’s clear the current system is not fit for purpose.”

The government has launched a round-the-clock “support hub” for transport operators wanting to check a passenger’s immigration status, but the “resolution centre” helpline for passengers operates only during British daytime and often has wait times of more than an hour.

The Home Office says 3.1 million people have so far accessed their eVisas this year by opening an online UK Visas and Immigration (UKVI) account, but has not said how many still need to do so. After the extended deadline, the old biometric residency permits (BRPs) will no longer work as proof of immigration status, although passport ink stamps and visa vignettes – which predate BRPs – should still be valid.

Campaigners say the eVisa rollout has been beset by technical problems. “We’ve seen government departments denying parents access to child benefit because they’re ‘not ready to accept eVisas’, and high street banks refusing to accept them as proof of status,” said Josephine Whitaker-Yilmaz of migrant rights charity Praxis. “These are the kinds of administrative errors that can push families over the brink into poverty, or even on to the streets.”

Some people have encountered technological obstacles to accessing their eVisa, such as not having a smartphone or a regular email account.

“Sometimes, even when people successfully create a UKVI account and receive the confirmation email, they still can’t access the eVisa because of technical issues,” said Sara Alsherif, programme manager with Open Rights Group. “There were problems where people could see their old application, not their new one. Some of these problems persist, including linking the refugee travel document to the eVisa.

“The Home Office’s delay will not fix the problems. In fact, it created additional problems and leaves many people without clear guidelines, especially after announcing that they would stop issuing new BRPs. That means that people have nothing to prove their right to work, rent, or re-enter, and the Home Office has left them in darkness.”