Repartitioning Time Machine by reallocating excess storage from other partitions

I have three partitions on my Drobo. Two partitions with a max of 17TB and one working as a Time Machine partition with 8TB. The T-M needs to be larger. Since I don’t use all the storage in either of the large partitions, I would like to allocate more storage to my Time Machine by reducing the size of the other two. Can I reallocate without losing data. Can that be done? And if so, how.

I too would like a reply to this question

Sadly no.
The only possible way (without resetting all your Drobo volumes) is to copy across your TM from its existing volume to one of the larger volumes, and then reconnect the copy within your apple-sphere. You will probably have to juggle your other data to achieve this.

@TwinTiger if their T-M backups reside on the “backup volume”, can they not copy the content elsewhere, disable backup in the dashboard interface (destroying that volume), re-enable it specifying a different size, then copy the backup data back to the new bigger backup volume?

From memory the backup volume is a special case & an arbitrary user defined size.

The other volumes won’t change reported max size of course.

That’s how I’d handle it for a Windows backup volume.