While I have
no idea where and when board members will be available
sept 13 starting 3/4pm in London would probably be best bet for
reasonable attendance.
The other limitation is that 21 days notice should be given. However that
can be
changed if 90% of members agree.
I thought it was 100% of members, but either way that's not difficult
since the members are pretty much the board and no-one else, since
they haven't been accepting applications.
We had a discussion on IRC about when and where would be a good time
to hold it and Saturday afternoon in London was, indeed, the best bet.
The 20th may be easier than the 13th (makes no difference to me), but
I think that's the last chance - the AGM has to be held before the
23rd (it has to be within 15 months of the last one, which was 23rd
June last year). I'm not sure what really happens if the board doesn't
call one within that time - they get put in the stocks and have rotten
tomatoes thrown at them, probably!