Wait times at Heathrow immigration were at an all-time high last summer, according to an investigation by Which? Travel.
Passengers complained of queues of up to five hours, with some collapsing due to lack of hydration and ventilation.
And the data tells a similar story: Border Force, which operates the border, aims to get 95% of EU (and UK) passengers through immigration in less than 25 minutes. But when we compared the available data for August and September over nearly 10 years, we found wait times have steadily worsened.
In 2012, Border Force was getting 100% of passengers through immigration within 25 minutes. In summer 2021, this had dropped to as low as 82% at Terminal 2.
The target for non-EU passengers is a less ambitious 45 minutes. But in September last year, only 62% of passengers in Terminal 3 made it through within this timeframe.
That's despite passenger numbers being artificially low due to Covid. In September 2021, 2.6 million used Heathrow, compared with pre-pandemic levels of 6.77 million passengers in September 2019.
The health checks introduced to limit the spread of Covid-19 are partly responsible. Border Force was tasked with inspecting passenger locator forms (needed to enter the country), along with vaccination status and proof of PCR tests to take after arrival.
The extra paperwork saw immigration checks increase from two to four minutes per person to an average of eight to 12 minutes.
The backlog at borders was so huge that the task of examining these documents was eventually delegated to airlines.
So why did the chaos in terminals continue? Since Brexit, the number of EU citizens being stopped at UK airports has skyrocketed.
In the first quarter of 2021 alone, a total of 3,294 EU citizens were stopped, compared with just 498 in the same period of 2020 - when air traffic was 20 times higher. That's an increase of 561%.
EU nationals now need to have settled status (or a visa) to live and work in the UK. But proving settled status is not straightforward, causing further delays.
The Home Office's own data also suggests that some nationalities are being targeted more than others.
Of the 7,249 EU citizens initially stopped at the border in the first six months of 2021 (at airports, ferry ports and the Eurotunnel), more than 60% of them (4,482) were Romanian. This was followed by Bulgarian (606), Albanian (451) and Polish (394).
Michaela Benson, Professor of public sociology at Lancaster University, believes Roma populations are being discriminated against. She told Which? Travel: 'These are really big numbers and we need to ask why they are so big. It is totally disproportionate. Some people are simply subject to greater scrutiny than others.'
A spokesperson for the Home Office responded: 'The claim that we have been racially profiling is false and unwarranted.
'If someone arrives at our border, intending to work here without the right to do so, the public rightly expects us to prevent them from entering - regardless of their nationality.These rules are applied fairly and solely on the basis of the individual's circumstances.'
The number of Border Force staff has gone up just 14% to handle this increased workload. Only 1,131 additional staff members have been recruited in the past year, despite the Home Office asserting it would need an extra 2,000 to 'take back control of our border'.
New rotas have been issued to plug the gaps, with shifts at the border extended from 10 to 12 hours. An unnamed Border Force official told the Daily Mail that many are suffering from exhaustion as a result.
Job ads for Border Force state that shifts can be up to 12 hours, and that early starts, nights, weekends and public holidays are all common. Hours can also vary in line with 'business requirements', so staff may be asked to stay longer if a flight is delayed.
A scathing review by a former employee on job site Indeed reads: 'If you have the stamina to work 16-hour-long night shifts or to wake up at 3am to go to work, then this job is manageable. Shift work, however, will eventually take its toll on your family life and health.'
Lucy Moreton from the Immigration Service Union (ISU) told us that the government was 'treading water' with recruitment.
She said: 'We never lack for applicants, but they seldom stay. The shifts are really damaging to health, so we are losing them as fast as we can recruit them.'
Queues are longer than they have ever been and complaints are at an all-time high, despite the fact passenger numbers were at an all-time low last summer.
It's a worry, particularly as more of us planned a foreign holiday after restrictions eased. The ISU tells us that the Home Office is now reviewing Border Force's punishing new shift patterns.
But while immigration officials continue to be understaffed and increased checks remain, we are in danger of facing more nightmarish queues to re-enter the country again this summer.