I have a mileage reservation from IAH - LAX - LIH in June in Economy. By that time my wife will be almost 7 months pregnant and I can't find any Business/First availability right now. I am thinking of paying for Economy plus upgrade to make sure she is comfortable for the long flight. However, I am still checking periodically on availability of Business/First mileage seats. Also, I am thinking of changing the date to leave a couple of days earlier. If I purchase the E+ upgrade, will they refund the cost if I change to business/first seats? Alternately, would the E+ upgrade transfer to a different date? Advice on this would be appreciated, thanks.