It might be that when you apply through Tesla you get 60 or 72 months depending on which bank they decide to use. For me and several other people who got 60 months, it had to do with a particular bank.I was recently able to get the 0.99% for 72 months at 100% financing with US Bank through Tesla.
In either case, Tesla shouldn't be advertising 72 months when it's not available for everyone, irrespective of good credit scores.