[ceph-users] Cephadm and Ceph versions

Hi I had a cluster on v13 (mimic) and have converted it to Octopus (15.2.3) and using Cephadm. In the dashboard is showing as all v15 What do I need to do with the Ceph rpms that are installed as they are all Ceph version 13. Do I remove them and install Ceph rpms with version 15 ? Regards Andy