Something

exten => _X,1,Set(stupidgroup=db(stupidgroup))
exten => _X,2,db(stupidgroup=$[${stupidgroup}+1])
exten => _X,3,gotoif($[{stupidgroup}>2,4,10)
exten => _X,4,Busy()
exten => _X,10,Dial(zap/g1/${EXTEN})
exten => h,1,Set(stupidgroup=db(stupidgroup))
exten => h,1,db(stupidgroup=$[${stupidgroup}-1])