Prophetic language is frequently fluid about sequences. Although this event appears to follow the Triumphant Messiah’s coming, we know that it actually precedes it, for it is happening today. “At that day” is simply a general reference to the end times. The gospel is being preached to the “remnant of this people,” whom we know as the Lamanites. Missionaries are also going to the “dispersed of my people” in various lands. The gathering of Israel is well underway.