Caller ID reformatting - only apply to 3 digit source patterns

[TMCentral Tech]

How do I create an Outbound caller ID reformatting pattern that only applies to 3 digits and does not match for anything longer than 3 digits? I would like to reformat internal extensions to the main outbound caller ID when they get forwarded to a mobile number.

Thus :

Call from extension 102 to extension 103 has caller ID of xxxxxxxxxx when it rings extension 103's mobile #
External call caller ID is passed unchanged when it rings extension 103's mobile #.

 

[cobaltit]

Did you see this article?

https://www.3cx.com/docs/cid-reformatting/

 

[TMCentral Tech]

I did see that, but my attempts to have my reformatting only apply when the CID is 3 digits did not work. When I tried (...) to match the 3 digit of the extension, it matched anything of 3 or more digits and replaced everything routed outbound with the replacement caller ID.

In testing, I had 600 as my test source pattern and it properly matched extension 600 but nothing else, but I'd rather not have to put an entry in for each of my extensions. If I made a rule for anything over 3 digits such as source pattern: (...)(.*) replacement pattern \1\2 and then a lower priority rule of (...), would that match anything over 3 digits to the first rule leaving anything not matching (...)(.*) (namely, my 3 digit extensions) to be handled by the second rule?

 

[TMCentral Tech]

Found my answer:
https://www.3cx.com/docs/multiple-outbound-caller-ids/

 

[cobaltit]

Good catch. I don't know that I've seen that article before.