Depending on how many numbers are involved (can't be too many if they remember them), consider using a CALL ROUTING TABLE based on caller ID...build a list of "special" numbers and have them ring direct to service, maybe with recall to main group if unanswered. We also use this to assure special treatment for biggest customers, sending them to a higher-priority hunt group.
By the way, you can use a caller ID CRT even if you're also using DID CRT, just flow one into the other.