Exo 23:10-13 BSB 10 For six years you are to sow your land and gather its produce, 11 but in the seventh year you must let it rest and lie fallow, so that the poor among your people may eat from the field and the wild animals may consume what they leave. Do the same with your vineyard and olive grove. 12 For six days you are to do your work, but on the seventh day you must cease, so that your ox and your donkey may rest and the son of your maidservant may be refreshed, as well as the foreign resident.

This is the first time the sabbatical year is mentioned. It is at Sinai, in the book of the covenant. It is not preceded or qualified by "once you come into the land". It is a command that stands on its own.

We are keeping the sabbatical this year, because by the timeline given in scripture, and confirmed by historical documents, this is the right year. I didnt plant much of anything last year, either, which is good because it wouldnt have been harvested before the seventh month.