I had a weird one on Serroco a few weeks ago, wish I'd screenshotted but as they say; hindsight is the most exact science.
Basically I move into a new area and there are 2 Acklays at about 0,20. I think "sweet, I'll go to the opposite side and there's no way they'll come for me" (out of perception range etc.). I find some bandits towards the north east of the map and start attacking and about 5 mins into my second delay they pop up towards the west south west of me with a north east travel indicator. Once they reach my y co-ordinate their movement indicator changes to east, directly for me, which was a little confusing since I have no idea how they can see me (range 10) unless there's some sort of tracking system in place. I'm hitting the scanners quite often at this point as you can imagine, hoping the delay will be over and I can get in my vehicle before they get in range (I've got a few low level faction owned troops ~70hp in my party), then at about range 6-7 they just disappear from the map?
I wanted to see if they were still in the map area or just purely disappeared, and I find them sitting stationary at their original position (or near enough that I assume it was their original position since I didn't log any of the events). For whatever reason they just teleported back to their start point, I genuinely thought some admin was playing games, if that's even possible.