Finder sidebar --> Get Info says external disk is macOS Extended "Journaled" only, but Disk Utility says the external disk is "Journaled, Encrypted" which it should be. The process of updating from Sierra to High Sierra strips away encryption?? I would think the updated process happened too fast for the process un-encrypt a disk. Note that my startup SSD "Get Info" information obtained from Finder Sidebar --> right-click "Get Info" matches Disk Utility info saying it's APFS (Encrypted). Before the update on Sierra my startup SSD was macOS Extended Journaled, Encrypted.