thanks for letting us know, the problem has been fixed now
To fix it for your existing installation, you habe to go to our manual setup page, by adding /setup/ to your EGroupware URL eg. https://example.org/egroupware/setup/
In the upper login box you enter
admin as user-name and the password you find in the file /var/lib/egroupware/egroupware-docker-install.log or /etc/egroupware.secret.
Once logged in go to Manage Applications, search for EPL-Features (aka stylite) and check deinstall and submit. Then check install to re-install and submit.
After logging out of setup and into regular EGroupware again as an administrator (eg. with user Administrator), you can check under Admin > Applications > EPL-Funktions > Licensekey that you got a correct test-license.
The problem was cause by our support-center installation already running under the upcomming 21.1 release.