Most of us love and embrace SOBRs as well as hardened Linux repos for obvious reasons.
Once in a while a SOBRs shifts out of balance because VBR cannot predict sizes of VMs and especially chains with changes.
Therefore, for a non-immutable repo we have ways to rebalance the SOBR: KB3100: Manually moving backup files between Scale-Out Backup Repository extents (veeam.com)
V12 will even bring us the conservation of space optimizations here: New in VBR v12: True per-machine backup files - vNote42
This though is and will not be an easy task for the hardened Linux repo, as it will prevent files from being moved between the extents.
I e.g. currently face a customers SOBR with one extent having 0% free while the others all have more than 80% free...
Question is: Did you ever face this challange? How did you solve it?
(Build chains from scratch? Disable immutability, reorg files, enable immutabilty?)