From the GP rules on BTFA webbie:
5. Anyone wishing to enter a Grand Prix Shoot who does not hold a BFTA card will pay an extra £2 and will be entered as un-graded. The £2 will go to the BFTA.
Does this mean someone who is unregistered with BTFA and hence has no BTFA number (maybe not a member of a club), or just someone who's left their card at home?