I am testing the possibility of migrating from an old Avaya phone system to AsteriskNow. The migration would cover several hundred phones--but spread out over several years. (Management wants to move buildings to the new phone system one by one as cables get cut or time permits.)

Two other directive is that extensions must not change and they want a GUI that other admins (non-Linux geeks) can manage.

They currently use 9XXX for all extensions.

We linked the Avaya and Asterisk box via PRI card and they both are communicating. From the Avaya side, if we move (for example) extension 9001 to Asterisk, we forward the call over the PRI to the AsteriskNow box and the SIP phone rings.

In AsteriskNow we have an outgoing rule '_9XXX' that routes all 4-digit extensions starting with 9 back to Avaya.

Here's the trouble. Dialing 9001 (the extension moved over to AsteriskNow) causes the call to be routed out the PRI to the Avaya box, then the Avaya box routes the call back to Asterisk, and Asterisk routes it to the SIP phone.

As we get more and more users switched over, it will use up more and more channels over the PRI card.

Is there a way I can ask Asterisk to check it's local extensions first--then forward off to the Avaya system if it starts with '_9XXX'? (I know how I can do it when editing the raw config files, I'm just looking for a way to do it in the GUI so other admins can manage it if necessary.)

As a last-ditch plan, I know I can specifically add '_9001' as an outgoing call rule and sent it directly to extension 9001--but I'd really hate to do that for several hundred phones