Hi Jacek,
No you are not missing anything and yes the v0.23.1-rc9 tag with the sources is the latest 0.23.1 version of ksqlDB.
The reason things look different now is that we are actually switching to a new release pipeline, so that's why some things might look different, but everything should still work fine. Please let me know if you encounter any other issues though related to the new release.
Thanks,
Natea