More than 250 people were detected in small boats crossing the Channel to the UK on Sunday after an apparent 11-day pause in crossings.
The Ministry of Defence (MoD) says 254 migrants were detected in seven small boats, as more people thought to be migrants were seen being brought into Dover on Bank Holiday Monday.
Sky News understands the number of migrants intercepted in Channel today will surpass the 254 of yesterday.
The figure takes this year's total for small boat crossings to at least 6,947 - more than three times the count of 2,004 at this time last year, and over six times the figure of 1,006 for the same period in 2020.
More than 28,000 migrants were detected making the perilous journey from France to the UK last year - 37 of whom drowned, according to the International Organisation for Migration - and a forecast has suggested the figure will almost double to nearly 60,000 by the end of 2022.
The MoD took control of migrant operations in April and was handed the responsibility when the government announced controversial plans to send some of the individuals making the journey to Rwanda.
Earlier this year Sky News revealed the Home Office was being investigated over the cases of approximately 850 individuals to see if the department broke privacy laws by unlawfully seizing their phones and extracting data from them.
The arrivals in Dover followed what appears to be an 11-day break in crossings between 20 April to 30 April, amid reports of strong winds and choppy seas.
Such breaks are not unusual and usually coincide with bad weather making the crossings more dangerous than they are normally.
Two longer gaps without crossings were recorded earlier this year before the Rwanda deal was announced.
Government challenged over Rwanda plans
A government spokesperson said: "The rise in dangerous Channel crossings is unacceptable.
"Not only are they an overt abuse of our immigration laws but they also impact on the UK taxpayer, risk lives and our ability to help refugees come to the UK via safe and legal routes."
It follows the passage into law last Thursday of the government's Nationality and Borders Bill, which allows Home Secretary Priti Patel to pursue what she described as a "world-first" agreement with Rwanda.
The deal means the east African nation can receive asylum seekers deemed by the UK to be inadmissible as they arrived "illegally" under new immigration rules, although these rules are already facing legal challenges.
The former home secretary and prime minister Theresa May was among those who criticised the plans on the grounds of "legality, practicality and efficacy", telling MPs she feared it could split up families and increase the trafficking of women and children.