I have a TRAID with 5 HDD and I want to add a 6th HDD to migrate from a TRAID (actual) to a TRAID+
The 6th disk of 16 TB is detected correctly and is largely bigger than the smaller HDD (1 TB) of the actual TRAID.

When I follow the instruction and go to Storage Pool and edit, the option to RAID level migration is grey out.

The only thing I can select is "add disk to RAID"
What do I miss to transform my TRAID to a TRAID+ ?
My model is the F6-424 Max and the TOS version is 6.0.794-01324
Thanks !
