Change homehost of an existing RAID array name?

My sole RAID5 array (/dev/md0) is shown in OMV with the name "Datacube:PrimeRAID" which is also reflected in the output of mdadm -D /dev/md0 on the command line.

I've since changed the hostname of my server from Datacube to something else. Changing the homehost to match it using mdadm seems simple enough, (the "PrimeRAID" part would stay the same) but I'm guessing that stopping the RAID array with OMV running is a Bad Idea™.

How can this be accomplished without running into any pitfalls?

I was advised that stopping the RAID was safe with OMV running. But I can't unmount the filesystem while it's in use, which means I can't lock the encrypted device below it, which means I can't stop the RAID below the encryption.

Am I stuck?

Update:

It dawned on me that what I needed was a bootable Debian USB stick to do this offline. Prepared one, booted from it, changed the homehost as desired by starting my array with the new settings, then stopping it.

Rebooted back into OMV and whoops, now /dev/md0 has turned into /dev/md127. That didn't stop LUKS decryption or the filesystem from working, but it was bugging me. I quickly found the fix:

Edit /etc/mdadm/mdadm.conf and change the array name to reflect the new homehost. (Although a comment states that OMV will overwrite changes, I was happy to find that did not happen.)

Then, run update-initramfs -u so the change is applied at system boot and the array is correctly started as /dev/md0 again.

Perfect. Problem solved.