Thanks for the replies folks.
Without giving away my home address, I'm riding over the Forth Road Bridge, through Edinburgh over the Granits to Innerleithen. Continuing down via Eskdalemuir, Longtown, Brampton, Alston, Bernard Castle, Skirting Darlo, Northallerton, North Cliffe, York, Cawood and to my folks on the East of Leeds. Mostly back roads but straight lines so I'm not meandering. Its a DIY 400. Setting off at a sensible time Saturday morning to arrive sensible time Sunday morning.
Though the weather is looking ok for the weekend, I am tempted to have a kip at my folks and leave on the bike again for Nottingham via the Humber Bridge to extend to a 600.