If I'm honest, I do have reservations about moving pregnant mums/young kittens, but if this is their only realistic chance of care/survival then I MIGHT be able to help Sat am:
OH is driving to Exeter... so looking at the map... he could make a detour south to join the M4 at Newbury (handover point) , then head west.
I do need to stress at this point, that he is working away from home today & I haven't been able to get in contact with him to ask if this is ok.
So just a possibility to bear in mind Angie/Lesley/ Koscha?
Jas