No official thread yet so I guess I'll add to here.
I've contacted the NYMBO people to see if they can put anything on, I think they themselves have event at Swaledale/wensleydale that weekend, so hoping to get some contacts or info. They have done Howardian's before.
But if not, I can look to create a 'route' (with help) in an MBO style.
(Mountain Bike Orienteering).
If I was doing it, it would be using phones for maps and controls, rather than providing a paper map.
Then use phones for getting to the controls
MapRun style.
Edit to add.
So it would be an open course and either a set route or a didn't all the controls and make your own route to get the most points in as set time.
This can include retrobike routes, I mean Gravel bike routes. Nothing needs more then 1.95" tyres and rigid forks around there.