Centurion permits you to complete a qualifying event after entering the race.
Just sign up for the event, and find some sort of marathon, between now and the date of the race.
OK I will throw out a few ideas.
The Dukeries Ultra in Nottinghamshire has 30 and 40 mile options, and it is a nice event, not too far from you.
The Northants Shires and Spires 35, was my first ultra, and I can recommend it.
If you want something sooner, and don't mind traveling, you could look at the Stort 30.
You might also look at the Compton Downland Challenge
Might I ask where you live Paul?
Forgive me, I assumed that the purpose of this forum, was to discuss ultra-running.
Might I ask where you live Helen?
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