SG: Mestama – Probably
WIY: Mestama (IIRC). Ayin Bava Basra 28B on the bottom (IIRC) where Rashi & Tos. deal with a set Shmittah. Assuming the timeline is right (granted, a large assumption) and that Yovel was not Noheg in Bayis Shaini, it’s a straight calculation. Others here would probably know more than I do about the Cheshbonos.