From the website - refund policy:
"Cancellation policy – adverse conditions
Dealing with adverse weather is part of the challenge of this series, however if the safety of riders and staff becomes an issue we may have to cancel an event. This will be announced on our website at 17.00 on the Thursday before the event, and riders will receive a refund minus an admin fee.
If a race is cancelled due to adverse or dangerous conditions any time after 17.00 on the Friday before the event we will refund a percentage of the entry fee taking in account any outlaid costs."
Trying to be fair about it - events do have some outlaid costs in the event of cancellation and these are run as non-profit. It really does help if people pre-enter tho so trying to be reasonable to all concerned. We don't leave debts on the hill.