Replacing Disks - Section is missing key details

[newhinton]

Source: https://docs.unraid.net/unraid-os/using-unraid-to/manage-storage/array/replacing-disks-in-array/#preparing-for-drive-replacement

First:

The "do not format"-warning seems important, but where/in what cases would i expect this message to show up? I was following the procedure as described, and i was never sure where i could do something wrong that would cause a reformat to appear. I think it would be helpful to make this warning more descriptive.

Second:

8. Click Start to begin the rebuild. Unraid copies data from the emulated disk to the new disk. If the new disk is larger, Unraid manages the extra space.

After i started the array in maintenance mode, what do i need to expect?
On 7.1.4, the array successfully starts into maintenance with the new disk properly assigned.
However: It shows up as emulated in the Array-Devices-overview, and the "Array Operations"-Section now has a
"SYNC - Sync will start Data-Rebuild."-Button.

This forum post clears up that there is a distinction between maintenance-mode and normal-mode. An explanation on this distinction, and the expected outcome of the actions would be helpful.

Thanks!