[Closed] Brecon Beast - Long & Short

Looking at the Brecon Beast this year and never having done it before (only ridden the Gap socially a couple of times), just wondering what the difference in entering for long or short actually is.

I've heard you can enter for the long route but decide to go with short part way round. In which case what difference does it make which you pick for entry?

If you enter long and do short, do you effectively get no time recorded or something like that?

Plus if you enter for short, could you change your mind and go with long during the ride?

I'm just uncertain on the fitness here, or rather my fitness 😀 . Though I can usually go on and on until I drop.