This is a lab system. There are 2 trunks on the system, line 000 & 001. Both of these lines are in the line pool. From the Norstar set I can select the Intercom button, dial the access code and get a line. I have tested by busying out each line and letting the pool select the other. This works both on the set and the ATA. The problem is when both lines are busy. The norstar set gets a busy, the ATA dead air.