Two cars - now on same billing schedule, even though they say it can't be done

It was time to call customer service and renew. Once again I asked the rep if we could get both cars on the same schedule - once again I was told that was simply not possible. I checked the website. The website agrees - it's not possible. So - I just renewed them both at the same time - got a credit for unused time on the one subscription, and in six months, I just have to make one phone call, instead of one phone call for each car a month apart. So - it can be done after all!