Good questions, Maisie!
Tom is a member (and fellow admin) on the Sangha of Buddhist Contemplatives Facebook page. He is proposing a meet-up (which Enida initially referred to in the Lounge).
The event has no connection with the OBC itself, although it is conceived as an event for people who have, or at some point have had, some connection with the OBC, and are therefore, inevitably, part of our wider sangha. Tom is planning the event for the UK. There is discussion underway here on OBCC for an event in North America as well.
Anyone may attend. It is tentatively planned for March 2015. This is very much a collective effort. The discussion around the UK event is occurring on the SBC Facebook group page. It is a closed group, but if you are on Facebook, I can add you to the group as a member.
Of course, Enida and I (and Isan, and a number of UK practitioners who are members of both internet sites) can provide additional information here, as it develops, as well.