Mishnayos Sheviis Perek 8 Mishnah 7

לא יביאנו לידי פסול (they will not cause [the vegetables]- to become invalid – so that the produce of the Sabbatical Year will not be wasted in the event the oil becomes unclean and must be burned) – foer if iet becomes invalid because of the oil of heave-offering, everything must be burned, and it is found that it will cause the fruit of the Seventh Year that it won’t be eaten.

ורבי שמעון מתיר – to bring holy/dedicated objects to the House of Impurity. But the Halakha is not according to Rabbi Shimon.

ואחרון אחרון נתפס בשביעית (The very last [produce obtained in this manner] is subjected to the laws of the Sabbatical Year) – How so? He purchased meat with the fruit/produce of the Seventh Year; the meat and the produce/fruit are removed in the Seventh Year, if he purchased fish with the meat, the meat is excluded and the fish subjected to the laws of the Seventh Year. If he acquired oil with the fish, the fish is excluded and the oil is subjected to the laws of the Seventh Year, and he is obligated to remove the fruit/produce and the oil, it is found that the very last thing acquired in this manner is subjected to the laws of the Seventh Year. But the produce/fruit of the Seventh Year itself is always forbidden, and we derive it from what is written (Leviticus 25:12): “For it is a jubilee. It shall be holy to you.” Just as what is holy takes hold upon/takes effect its monetary value, so even the Seventh year takes hold upon/takes effect on its monetary value. Or, just as the holiness takes hold upon its monetary value and it goes to unconsecrated produce, even the Seventh Year takes hold upon its monetary value and it goes to unconsecrated produce, the inference teaches us – "תהיה"/it shall be [holy unto you], it will be in its status.