Are we talking this side of Xmas or after? The thaw is predicted to start on boxing day so I imagine it would be fine to drive on at least the main roads on and after say the 27th.
One of my colleagues did Penzance and a horde of other spots in Cornwall, from Bristol, yesterday with no worries in a rwd Transit. Another has been to Lossiemouth today.
No issues on main roads at all.
Edited by Six Fiend on Wednesday 22 December 21:57