They should not be allowed to set foot on English soil. One of the many liners not being used should be at anchor in the channel & they should be put onboard for processing, those that don't pass muster, which I think will be a large proportion, should be then taken to an east African country, to whom a fee is paid to lodge them.
Once the process is under way & the word is out, the rubber dinghies will stop coming.
A similar process worked in Australia, it isn't rocket-science.