Sforno on Exodus 16:35/ספורנו על שמות ט״ז:ל״ה

1אכלו את המן, in lieu of bread made from wheat or other cereals. The Israelites themselves testified to this in Numbers 11,6 when they said (complainingly) בלתי אל המן עינינו, “all we have to look at is the manna.”

2עד בואם אל ארץ נושבת, inhabited countries, i.e. the lands conquered from Sichon and Og on the east bank of the Jordan river. Once they had taken over these lands they also ate regular bread. [a period of possibly six months before they crossed the Jordan. Ed.]

3את המן אכלו עד בואם אל קצה ארץ כנען, the word את, meaning “with, in addition,” alludes to the fact that they no longer ate manna exclusively. We find further confirmation of this in Joshua 5,11-12 ויאכלו מעבור הארץ ממחרת הפסח...וישבות המן ממחרת, “they ate from the produce of the land, etc.,…the manna stopped on the morrow after the Passover.”