We are UK based and trialling 3CX as an alternative to our normal pbxs. Our SIP provider presents the incoming calls in the format +441234567890. I want to replace this with 01234567890. I have put this on the Incoming CID rewrite options on the trunk Source +44(XXXXXXXXX)(.*) Replace 0(XXXXXXXXX)(.*) This does not work. So I suspect my formatting is wrong but I'm not sure how.