Pete, you indicated that you were upgrading to an R6 or R7 ACS along with Partner Messaging. In this situation, the ACS becomes the processor, and the 206 modules that currently make up your entire phone system can go into the carrier and become expansion modules for the ACS. With an ACS R6 and 5-slot carrier, this would give you a 7x20 capacity (9x21 with an R7)