Weird Unit Spawning Glitch in Ch. 15 Eirika Route

[RunawaySSB]

I was playing Sacred Stones on my 3DS today, attemping a Seth pseudo-solo. I got to Chapter 15 and had to restart a couple of times. However, on my 3rd or 4th restart, I noticed the pattern in which Ephraim, Duessel and Knoll joined the battle had changed from its typical diagonally-down-from-the-left formation; instead, all three units joined in a straight vertical line directly against the left wall of the map. On the run before this, I placed Ephraim in the bottom-left corner of the map on low HP (and mistakenly had him Wait instead of heal himself, which prompted the restart to begin with), but that's all I can remember. I haven't been able to replicate this anomaly. I have pictures and a video proving the turn count if necessary. Does anyone else remember having something weird like this happen?

Edited January 28 by RunawaySSB
clarification

[eclipse]

Pictures would help.  It might have to do with where the enemies were, but that's just a blind guess on my part.