It seems that there is an action for the charm which does exactly what Jorge described in #4
`juju run-action cinder/leader remove-services`


`  removed: cinder@cinder-ceph-hdd,cinder@cinder-ceph-hdd,cinder@cinder-ceph-flash,cinder@cinder-ceph-flash,cinder@cinder-ceph-flash,cinder@cinder-ceph-hdd
`

From
```
+------------------+--------------------------+------+---------+-------+----------------------------+---------+-----------------+---------------+
| Binary           | Host                     | Zone | Status  | State | Updated_at                 | Cluster | Disabled Reason | Backend State |
+------------------+--------------------------+------+---------+-------+----------------------------+---------+-----------------+---------------+
| cinder-scheduler | cinder                   | nova | enabled | up    | 2021-08-04T16:00:00.000000 | -       | -               |               |
| cinder-volume    | cinder@cinder-ceph-flash | nova | enabled | down  | 2021-08-04T14:12:03.000000 | -       | -               | up            |
| cinder-volume    | cinder@cinder-ceph-flash | nova | enabled | down  | 2021-08-04T14:12:08.000000 | -       | -               | up            |
| cinder-volume    | cinder@cinder-ceph-flash | nova | enabled | up    | 2021-08-04T15:59:57.000000 | -       | -               | up            |
| cinder-volume    | cinder@cinder-ceph-hdd   | nova | enabled | down  | 2021-08-04T14:11:58.000000 | -       | -               | up            |
| cinder-volume    | cinder@cinder-ceph-hdd   | nova | enabled | down  | 2021-08-04T14:12:04.000000 | -       | -               | up            |
| cinder-volume    | cinder@cinder-ceph-hdd   | nova | enabled | up    | 2021-08-04T15:59:57.000000 | -       | -               | up            |
+------------------+--------------------------+------+---------+-------+----------------------------+---------+-----------------+---------------+
```

to


```
Binary           Host                                 Zone             Status     State Updated At           RPC Version  Object Version  Cluster                             
cinder-scheduler cinder                               nova             enabled    :-)   2021-08-04 16:54:27  3.12         1.38                                                
cinder-volume    cinder@cinder-ceph-hdd               nova             enabled    :-)   2021-08-04 16:54:26  3.16         1.38                                                
cinder-volume    cinder@cinder-ceph-hdd               nova             enabled    :-)   2021-08-04 16:54:26  3.16         1.38                                                
cinder-volume    cinder@cinder-ceph-hdd               nova             enabled    :-)   2021-08-04 16:54:27  3.16         1.38                                                
cinder-volume    cinder@cinder-ceph-flash             nova             enabled    :-)   2021-08-04 16:54:26  3.16         1.38                                                
cinder-volume    cinder@cinder-ceph-flash             nova             enabled    :-)   2021-08-04 16:54:26  3.16         1.38                                                
cinder-volume    cinder@cinder-ceph-flash             nova             enabled    :-)   2021-08-04 16:54:27  3.16         1.38                                                
```