Can I upgrade data drives now to larger capacity than parity and upgrade parity drives later?

[Griz]

I have an array with all 6TB disks and dual parity.    I have 3 18TB drives on hand that I was about to use to upgrade parity, but when I ran a parity check before starting, 2 of my data drives started racking up read errors and re-allocated sectors.

 

Can I rebuild those failing drives now with the new 18 TB disks and then upgrade my parity drives to 18 TB later?   Will the data drives then be able to use their full capacity after the parity drives are upgraded?

[itimpi]

No data drive can be larger than the smallest parity drive.

 

you can use the Parity Swap procedure to simultaneously upgrade a parity drive to a larger one, and use the old parity drive to replace an array data drive.   With dual parity you can do this to two drives at the same time.  
 

After a data drive has been rebuilt then if it is a larger drive than the one it replaces the file system then gets expanded to fill the whole disk.