In my past two preseason games I have had two left tackles draw at least 4 targets in the passing game. I'm not sure whether they are lining up as WR/TE, or if they are doing this from the LT position. Either way, it should not be happening. I checked my depth chart and have no issues there. The only thing I can think of is that I have only one active TE due to injury, so maybe they are playing TE due to that, but the game should be smarter than that. Put in a FB/WR/RB, someone who should be touching the ball.

It usually happens during the preseason when players aren't in shape plus if you don't have a solid depth chart like you mentioned. I've seen offensive and defensive linemen playing CB when I didn't have extra players on my depth chart. I fixed this issue by simply signing more players but I agree it shouldn't be that extreme where they just add a lineman over other skill players.

The AI does its best to keep the same position groups in the substitution, if you have it falling back to put linemen in skill positions then you literally are out of skill position players. Remember that during preseason you can have 60 active players - so be sure you are taking advantage of that unless your cap space just doesn't allow it.