It's actually in the rules that those on Club Plate registration have read and understand.
For those who do not quite get it, Clause 24 of the RULES covers this situation:
24. Vehicles may be used on a road or road related areas for:
a) Events listed under ‘coming events’ in the Club magazine, or ‘coming events’ on the Club website, or notified via official correspondence from the Committee.
An email has been sent to all members from a Committee member (myself) on behalf of the President encouraging members to come in club attire and in the Mustang if they so wish.
Phil Preston