Let's put it this way:
the furthest cycling activity from Audax is indoor cycling on a stationary bike, the second furthest is cycling around a track and the third furthest is Everesting.
Everesting does not recognise Audax, in the sense that you could climb 8848 vertical metres (or whatever is the altitude of Everest) as part of a randonnee but that would not count, so why should the Audax UK magazine endorse this activity with a cover quoting even George Mallory?
As for the challenge, it is beyond me, chapeau to anyone who Everested, but it has been done to death... once I looked whether there was a meaningful climb in the UK that had not been Everested yet and the answer is no, they've all been everested already...
I think Arrivee should be about long distance cycling, end of...
Rant over