Are you sure the presets are not there? The easiest way to get to them is to use the expanded grade bin view and select the Global setting. In the directory browser at the upper left you should see the Global Grade bin listed. Just below that you should be able to open folder called Grade Bin Presets. Here are your 170 preset looks in various subfolders. Lets us know!
I just realized I’ve been dragging the Preset Grades into my local Scene Grade, thus removing them from the Presets bin. I assumed this would copy the grade into my local project, but it seems to permanently remove it from the Presets! Is there a way to quickly restore the Presets to their default set?