Yes you are correct, aside from the Drobo B1200i which supports volume size as large as 64 TB after its recent firmware update.
This is a new release of Drobo firmware for Drobo B1200i.
• Increased the capacity of the storage pool from 32TB to 128TB.
• Users can now create volumes as large as 64TB on current supported platforms.
• Added support for higher drive capacities (e.g. 6TB).
• Improved relayouts to be up to 8x faster.
• Improved collection of Diagnostic files under heavy loads.
• Fixed a crash caused when BitLocker or SyncToy were used.
• General stability and speed improvements.
• Better handling of bad disks
Because the PRO is a legacy, end of life product, we will not be releasing any new firmware for the unit. Kelvin is correct, we did just release firmware for the B1200i that can support 64 TB volumes with storage pools up to 128 TB. Also remember the volume limitations are based on the file system.
Will the 64TB volume support be coming to the B800i or B800fs?
I have a DroboPro and the 16TB volume size limit has been a pain for a few years now. It’s even worse now that 8TB drives are commercially available. Going to a much more expensive 12 bay product like the b1200i is overkill for my needs