As Oliver Cowdery copied the text from 𝓞 into 𝓟, he initially wrote “and they which shall come upon other lands”, undoubtedly because he had just written “both they which shall come upon this land”. Oliver immediately corrected the text by crossing out the repeated come and supralinearly inserting be (there is no change in the level of ink flow). The original manuscript, which is not extant here, undoubtedly read be. The contrast here is between those who came to the promised land and those who did not.
Summary: Maintain the corrected reading in 𝓟 for 2 Nephi 27:1 (“they which shall be upon other lands”).