Hi Mark,
I have a customer with a similar requirement. We created a separate trunk group for each site to manage the outbound CLIs. We then set that trunk group as the first choice for the site for outbound calls. This way the default CLI works along with configured DDI/CLI per user assuming the trunk group is configured for this. If your Edge connects direct to the service provider it will depend on whether the service provider will accept multiple trunk groups. In this configuration we have a pair of SBCs that accept DDI ranges for 80+ sites with their own ranges.
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Richard Chandler
G3 Comms Ltd
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