Cambodian coin date difference? [solved]

Hi, have a look at this coin:

N#183140

While the date range at the bottom (year line) is correct, the date range at the right (Features → Years) is complete nonsense. And while I know how to change the date range at the bottom, I have no idea how to change the one at the right. I didn't even know they're separate things … which doesn't even make sense. It's also the right year that's searched by when you look for specific years.

So how can the right date be changed and why is it even different?

Not sure exactly how, but the reason has to do with the calendar used - India - Fasli era.  The dates 1847-1860 are Gregorian.  Adding 590 to Fasli year comes to Gregorian year.

Requested change to gregorian for now.