This is more related to your "losing" your E+ seats due to equipment change. After I got burned by this a couple of times, I tried to be more diligent in first thinking thru 1) if there was an equipment change what would be the likely substitute(s) and
2)then selecting seats that would always "exist" within the widest range of equipment possibilities. Its not a perfect scheme, but it has saved me some heartburn a few times.