Because of an issue, I decided to format (erase/delete) the HD (1TB Fusion drive) on my 2017 iMac, and re-install Mac OS. Following the instructions from Apple support, and going thru Disk Utility, I started the deleting of the volume called "Macintosh HD" about 8 hours ago (approx. 6:30 am MDT, Oct. 23, 2018). As of this writing, the computer still shows "Deleting Volume" is still in progress. How long does it take to erase 1TB drive? Should I abort this attempt and start over, or give it more time?