Yahoo new position: FC. Not covered in their Help Section.

Anyone notice the new "FC" position in their league settings? I checked the Yahoo KB https://help.yahoo.com/kb/SLN6927.html but it doesn't address what this new position is eligible for. Other google links say it's for frontcourt players, so PF/C, but it makes more sense to me if it was a flex for F/C. Essentially, I thought this was a fix for not having to use 2 C... does anyone know for certain what FC is used for?