There was recent surprise over the substitution rules in official matches and the option of ofiicial matches with uneven teams.
Match rules: http://forums.bzflag.org/viewtopic.php?f=103&t=13226

Both were posted &/or discussed in the forums:
sub discussion: http://forums.bzflag.org/viewtopic.php?f=103&t=17357
Uneven match option: http://forums.bzflag.org/viewtopic.php?f=103&t=18238

Also a reminder to read the Ban Penalty thread on forums:
http://forums.bzflag.org/viewtopic.php?f=103&t=13185

Important to read the forums, Home, Rules, FAQ pages here.