We have a Mitel SX-200 LW17 at work with a PRI/T1 with 100 consecutive DIDs (XXX-2500 to XXX-2599) and two outliers. One of the outliers is our main number and the other our fax. All of our calls go out with the CID of the first number in our DID block (XXX-2500), but we would like to make all calls go out with the CID of the main number (YYY-6400). Is this possible?