Plenty of nonsense in that route including several wrong turns and what not. From memory:-
Stay on the A7 between Longtown and Langholm - the road to the East is unnecessary hills
Avoid the A66 from Middleton Tyas (go via Melsonby), otherwise (with the above deviation) the route North of there is lovely. I love the B709
The visit to Coxwold is unnecessary, but the Howardian Hills are fun
No need to visit the Thorne Travelodge (I stopped overnight there and at a B&B in Alston).
Lincoln was a wander looking for some Fish & Chips
The road through Ruskington was my least favourite road ever, and I'm not afraid of busy roads.
(GPS ran out of space on the run in to Edinburgh but to make it the right distance I had to carry on through to North Berwick and then get the train back in to Edinburgh, on St. Patrick's day.)
Save it and stitch it together at a later date, better than losing it all (which Garmins can do when you approach/go-over 400k).
I did it back in 2009 over 3 days to recce the LEL route for the organiser and I went through Thirsk: https://www.strava.com/activities/163178655
Plenty of nonsense in that route including several wrong turns and what not. From memory:-
(GPS ran out of space on the run in to Edinburgh but to make it the right distance I had to carry on through to North Berwick and then get the train back in to Edinburgh, on St. Patrick's day.)