Tom the below is from the booking in page, you can turn up but they recommend you book. Also cheaper if you book in now.
"Booking in for non regional support classes is not required but recommended so we can gauge the interest.
Non regional support classes fees are the same as a Normal club day, £5 per person (Members) or £10 non members payable either on the day or via paypal to
info@bmrcc.co.uk. Booking in on the day is available but @ £12.
Note though that the support class is only for those not entering a 4wd.