Question regarding the digit manipulation for the outgoing caller ID

I have a question regarding the digit manipulation for the outgoing caller ID. Our AltiGen system has an app that allows a user to use their mobile phone as their office extension. When another extension in the office calls that user’s 3 (or 4) digit extension, the mobile phone rings and the caller’s 3-digit extension number are displayed as the caller ID. Earlier this year, T-Mobile implemented a change and is now blocking all calls with less than 10 or 11 digits in the caller ID. Is there a way in the digit manipulation to tell the system if the outgoing caller ID is 3 digits (212), to add 7 digits (8089521), so the outgoing call ID becomes 8089521212? If so, can you please send me the documentation for the parameters for digit manipulation?

Yes, you can do this regular expression in the routeset definition file remapped_calling: /^([0-9]{3})$/8089521\1/

This means if the calling has 3 digits only, then add 8089521 in front of it to make it 10 digits