A method of regulating data transmissions used with telematics-equipped vehicles. The steps include establishing a period of anticipated call center service outage, notifying a plurality of telematics units of the period of anticipated call center service outage, storing that outage information at the plurality of telematics units, and then when a call from the vehicle to the call center is desired during the service outage, the process implements a call handling procedure that delays most calls until the call center is available, but that provides alternative call solutions for urgent or occupant-placed calls. Once the call center is available, postponed calls can be staggered to avoid a large initial spike in calls received at the call center.