I would shorten this 1 short sentences. There is a ton of irrelevant information or information which EY already has in front of it, e.g., how much you fly and what you spend. The information you wish to convey is lost in the jumble.
I would send a note which says.
"As to your 787 in F, the footrest should be raised by 4-5 inches so that a carry-on may be slid underneath."
Don't expect more than a cut & paste answer as it's not as though any carrier is going to redesign its soft product for you.