Thank you for your responses to our questions. We do have a particular finding regarding the MB992SKR-B and how the RAID 1 array displays in BIOS. Depending on the BIOS, where the RAID1 array appears in the BIOS may vary. In our testing, the BIOS for the ASUS P7P550-E LX display the RAID 1 array under a hardware section, and will not show up under the SATA connections. However, the BIOS of the Gigabyte GA-H170-D3HP shows the RAID 1 array under the SATA connections. While in RAID 1, individual drives in the unit are not shown in BIOS. Additionally, depending on the BIOS, it might not be possible to boot from the RAID array.
For your case of the RAID 1 array not showing up in BIOS, it might be in a different section in the BIOS. On your bullet point on setting the unit to RAID1 without any drives than inserting drives, if hot swap is not enabled on the SATA port the unit uses in BIOS, that port will not look for inserted drives after boot up and would require a full power cycle of the computer to detect the drives inside.
I do have some additional questions on usage of the product you have.
-Are you using the RAID1 function of the unit to clone boot drives? The RAID1 function of the unit is not designed for cloning.
-What motherboard are you using with the unit?
-Does the SATA port you are connecting the unit support port multiplication? In order to see and use both drives in JBOD mode, port multiplication function is needed on the SATA port, as the MB992SKR-B uses a single SATA connection to connect both drives to the computer.
-Are you able to find the drives in a RAID 1 array in BIOS?
Please follow up on these questions so we have a better idea on your case.