Each T3 has a total of 256 HDLC resources or 256 channels. So when you configure 10 T1 controllers with full channel-group config of 24 time slots each, that takes the total of HDLC resources or the channels consumed to 10x24=240 . So 10 is the maximum number of T1 controllers configured for channel-group. With 240 consumed, we are left with 16 resources/channels , so on the 11th controller we can actually go to a max of "channel-group x timeslots 1-16". After that,since we will run out of HDLC/channels, it will give us that error mesg.
