We are looking into replacing our existing 3com NBX system. We have two offices connection via an MPLS. Each office has a 3com NBX server. Main office has a PRI with DID. Remote office has POTS lines. The 3com servers are connected via 3 virtual tie lines for extension and call routing between offices. I am evaluating 3cx as a possible replacement. What capability/feature of 3cx would i use to duplicate the virtual tie line connectivity? Also, would we be able to allow incoming calls for either office to be routed to an attendent in one or the other office (like for lunch coverage)?