I’m not seeing how that has anything to do with the licensing. It would be trivial to either block connections from newer clients with an appropriate message or to just prevent the server from starting if it’s outdated. Having threads from people wondering why their server refuse to start once a month isn’t helping to reduce support workload, either.
The only reason I see to “solve” this via expiring licenses is if you plan to not include free licenses in future versions (or at least not with the same terms) and want to prevent people to continue using the beta servers license for free.
This is still a beta License not a free license
According to TeamSpeaks own release notes, it’s a “Default license”, not a beta license. Giving people not even two weeks to update the server before literally breaking it is simply not acceptable, even during a beta.
I don’t get why you’d defend this practice, it’s simply not in anyones interest to regularly break peoples servers.