There is no method to switch between spindle and flash disks without losing data on the H200. There is no supported method to upgrade disk size even if you were going from spindle to spindle of the same interface type(SAS, SATA).
You will need to back up any important data. Changing the disks will require deleting and creating a new RAID array.
Also, I don't think the H200 supports drive mixing across the controller. So, you can't create a second RAID 1 with the SSDs and clone/copy the disks on the H200. You can check the controller manual to verify.
Dell EMC, Enterprise Engineer
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