Was it a stitch-up for Cyclists in Southwark to be asked to cancel a Cutty Sark ride?

With 38 cyclists (plus an all-male splinter group of 5 doing a ride up the Lee Valley) turning up at Cutty Sark Gardens on Saturday 16th Feb at 9.30am for a third Saturday social ride, how are we going to be able to register who these people are and how are we going to be able to organise what they do?