Most of my diving is done on boats where there have been 'drop outs' or 'couldn't get enoughs'. Once you have dived a few times with a Skipper they are usually happier about having you on the known reserves list
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If Brighton/Eastbourne are within your proposed area then PM me your email address and I can send you a couple of links.
Pls bear in mind, as I'm sure you do anyway, that you make sure you and your buddies are up to the dive being done. The resposibility will be yours NOT the original boat booker or the skipper.
I know Andy, Taurus, Dover has his own web site with a virtual Club to which all members rcv emails about bookings/places etc.