AlanG wrote this on the Bearbones forum in Oct 2016:
It’s NOW just over 5 weeks until I will start taking requests for places on the 2017 group start. Still not too late to get a qualifying ride in!
These include Lakeland 200, Cairngorms Loop and Yorkshire Dales 300. All should have been completed inside the time limits. I’ll also accept the northern or middle loop of the HT550. The main reason for having these “qualifiers” is for you to know what you are getting into and the best way is to have done large parts of the route itself. GPX files/links to Strava activities accepted as “proof”.
Finishers from the last three editions (since HT became 550 miles) will have a guaranteed place. An ITT finish also assures you of a place. This year I will take up to 60 names again and expect 40-50 to make the start line come May 27th. I’ll keep 10 places for women but won’t limit it to that should there be more female applicants. Also a minimum of 10 places will be for overseas riders, who should have experience of tough bikepacking routes/races where they are from.
The route for 2017 will be almost identical to this year.
I would imagine things will be similar for 2018.
Anyway, I'm on this year's group start so will report back on how I get on.