I used to drive from Loughborough down to J27 and beyond all the time, hitting Bristol after 20:00 and you should have a clear run of it.
That said if you don’t have a clear run the final stretch to Woolacombe is not a straight blast rather its about as far from straight as you can get and I’d suggest not driving it if you’re tired.
We live halfway between Tiverton & Dulverton and have a converted loft which you and the wife could kip over in if you’ve had a crappy drive.
We have a teething 8mth old daughter so there’s a high likelihood that we’ll be up late. Oh we also have a bengal cat but don’t mind him. Email in profile, drop me a line if we can help. 🙂