Harvey, I can't help a lot but I have tested the route splitting on a longer route - no problem, an auto-generated route with your same start & end points - no problem so the system does seem to be working - there just appears to be an issue with your route. Even replacing your overnight stops with CT recommended ones makes no change. (By the way, my error msg is: "Sorry, the route wasn't saved because an error occurred: error"

If this is urgent for you, you could try loading the whole route and for each 'day' deleting before and after the start & end point. Save this, reopen the 'Master' and repeat for each stage. If you do this all in one folder you can check the map view to make sure you don't miss a stage. 

Interestingly, if you 'cancel' the first overnight, the system will download the first 4 days. This doesn't seem to work for the other overnight stops. 

I’ll look into exactly why it’s happening but, for now, if you click “Show turn-by-turn instructions” at the bottom left, that should allow you to save it split into multiple days.

I’ve identified the issue and it should be fine now. Thanks for spotting!