Someone

on *:INVITE:#:{
notice $chan Please wait for an avalable bot
 if ($me == etcbot1 && $chan(0)) == 30) {
 msg [ss]etcbot2 join $chan
}
 elseif ($me == [ss]etcbot2 && $chan(0)) == 30) {
 msg [pc]etcbot3 join $chan
}
 elseif ($me == [pc]etcbot3 && $chan(0)) == 30) {
 msg [cw]etcbot4 join $chan
}
 elseif ($me == [cw]etcbot4 && $chan(0)) == 30) {
 notice $chan All bot are full, invite at another time
 }
}

of *:TEXT:join *:?:{
if ($me == [ss]etcbot2 && $nick == etcbot1) {
join $1
}
elseif ($me == [pc]etcbot3 && $nick == [ss]etcbot2) {
join $1
}
 elseif $me == [cw]etcbot4 && $nick == [pc]etcbot3) {
join $1
 }
}