There are signs smugglers have been putting increasing numbers of people into each boat.
In 2018, there was an average of seven people per boat – but last year, that had risen to 62.
Last Tuesday, 173 migrants had to be rescued from a single boat, which caught fire.
Some 258 migrants arrived in the UK in four boats on Saturday, according to Home Office figures, with 423 arriving in five boats on Sunday.
However, the number of crossings overall is on course to be lower this year.
The provisional total for the number who have made the crossing so far in 2026 is 15,242, which is down by 43%, while the number of boats that have successfully crossed is down by 49%.
Last month, the Home Office recorded the lowest number of crossings in July since 2020.
Officials think this is partly because they have managed to disrupt the supply of small boats and engines to the people smugglers, with 1,100 seized since Labour came to power.
Officials claim that with the sophisticated surveillance and reconnaissance operation now operating over the Channel, “unintercepted” beach landings have ended.