Well, there you there - couldn't have put it better myself. Five and a bit years ago..................
Virtually all of the route went as planned, apart from sticking to A roads south of Edinburgh to shorten the route, and the next day finding part of the planned route was actually a dead-end through a new business park rather than the road that Google had showed, meaning a detour.
Day 1. Sat. 18th. Durness to Dingwall - 94.3 miles 4,356 ft climbing in 7:01 Hours Av. Speed 13.4 mph Max 35.8 mph
Day 2. Sun. 19th. Dingwall to Blair Atholl - 96.7 miles 5,492 ft climbing in 7:07 hours Av. Speed 13.3 mph Max 30.9 mph
Day 3. Mon. 20th. Blair Atholl to Edinburgh - 79.3 miles 4,809 ft climbing in 6:08 hours Av. Speed 12.9 mph Max 33.8 mph
Day 4. Tue. 21st. Edinburgh to Hexham - 104 miles 11,663 ft climbing in 7:25 hours Av. Speed 14.0 mph Max 36.1 mph
Day 5. Wed. 22nd. Hexham to Thirsk - 82.8 miles 4,855 ft climbing in 6:11 hours Av. Speed 13.3 mph Max 38.4 mph
Day 6. Thu. 23rd. Thirsk to Grantham - 126 miles 1,558 ft climbing in 8:36 hours Av. Speed 14.8 mph Max 27.0 mph
Day 7. Fri. 24th. Grantham to Luton - 102 miles 4,655 ft climbing in 7:23 hours Av. Speed 13.5 mph Max speed 33.4 mph
Day 8. Sat. 25th. Luton to Dover - 119 miles 5,731 ft climbing in 8:23 hours Av. Speed 14.1 mph Max speed 33.9 mph
I've got the gpx routes if you want. When planning the route I basically worked on around 100 miles per day as an average, and tried to find a decent size town at around that distance, to then find accommodation. In Scotland, when ringing around in January for the planned date in June, often my 1st & 2nd choice preferred B&B would say they were fully booked and had been for months. And that was before I mentioned being a cyclist, so clearly the popular places go quickly.
We each carried one pannier with 3 lots of cycling clothes which we washed overnight, which worked fine, as they'd dry on the bike. Midges weren't really an issue. And everything generally went very well, so afterwards there wasn't anything I would have really changed, as the route was just about as good as possible.