So Peterborough is now in tier 4

after being in tier 2 below us only 7 days ago. Travel is barred BUT I think my drivers can still come in to work .
We have a bit of work in for xmas day and boxing day BUT I suspect the majority of it will now cancel as some of the destinations are in tier 4 since Peterborough extends to the outskirts of the town.
If people don't cancel and I still take them could we be held liable for flouting xmas regulations ?
The biggest conundrum is the eastern European builders because they live in London and are planning to travel up by train to Peterborough Monday am to work in Stamford and then be taken back to their accommodation in Peterborough on Monday night (they are now renting a house on the welland estate). As far as I can ascertain you are not allowed to stay overnight if you travel from a T4 area but then they barely speak a word of English so explaining that would be an issue!
Next week is going to be a big headache!