London Edinburgh London 2025

[matticus]

High Easter is one such where the Sign Posts shown on the sheets seem not to exist.

Have you actually checked this on the ground? LEL2025 probably had more people pre-riding and checking the route-sheet than most rides ever staged in the UK.
Of course errors do sometimes creep in, so it's wise to be prepared - as it sounds like you usually are! - and be aware that by Sep 2026 a number of small things (like sign-posting, or traffic lights, or business names) could have changed since July 2025.

( I rode LEL'09 entirely on route-sheet without a hiccup, and similar for lots of long events in my first few years of UK audaxen. )

 

[Dogtrousers]

Maybe do a dual approach. You can load the routes in your Garmin, and get it to navigate, but have that simply as backup. Don't display the map on the screen and use the route sheet cues that you prefer. The GPS will chirp approaching a turn which can complement your route sheet and it will buzz if you go off course. Noises that aren't particularly intrusive and you can ignore if you like.

 

[blackrat]

That might be an option.
I do like to treat each new ride I do as a story so I add interesting titbits to the cue sheet about the villages and towns I expect to pass through as well as landmarks confirming turn locations. It can be very boring just looking at the road, so taking the time to learn interesting facts about a location whilst riding through takes away some of the monotony and adds to the pleasure.