Thanks, Dave, that clears it up! For now, I've changed the start day for trading to Jan 20 (10 days before we meet in person), and if we have any latecomers signing up for the swap, I'll treemail you with their usernames.
For the record, I think that would be a useful option, perhaps something to add to the control panel? It could be a set-up option, whether or not to allow people to sign up after trading has begun.
Better yet would be if the host could manually add names, letting the host keep up with newcomers and just adding a measure of control... in fact, it might not be bad to be able to let the host remove names from the participant list also, just in case a "bad apple" pops up. I'm sure a lot of this has already been discussed... I've tried to find a thread about it, will look again.
Thank you!!
