Frustrating

Your license policy is really frustrating.
I bought the expensive Teamviewer 12 license less than a year ago and I'm totally fine with it's features, I don't need the new fancy Teamviewer 13 features, but as soons as one of my customers installs Teamviewer 13 on one of his or her systems, I can't access it anymore!

I cannot force my customers to use Teamviewer 12 only and by your ridiculous license policy I am now forces to upgrade to Teamviewer 13 and upgrading my license even so I don't need any of your new features at all!
You're advertising that there is no need for a subscription when buying Teamviewer, but with this license policy, there is not much difference...

And then you're sending me an e-mail with a "special offer" of upgrading my license to version 13 for 202 EUR insteadt of 209 EUR - wow...7 EUR off, how generous...