1)
Until when did they undertake to remain in Eretz Cana'an?
1.
Rashi (on Pasuk 24): Until the land was conquered and distributed. 1
1
Rashi: Even though Moshe only stipulated "until the land has been conquered" (See Pasuk 22) and not until after the distribution. See Oznayim la'Torah on Pasuk 19, who explains how, by remaining during the years of distribution, they would be able to assist with the distribution - seeing as, as opposed to the nine and a half tribes - they were not biased.