Originally Posted by
CASAFlyer
If you wish to purchase E+ better to do it sooner than later, since the best seats disappears. The fee is non-refundable though, so keep that in mind if your plans are not firm.
In my experience, the non-refundable part means that you can't change your mind and decide you want to fly in E- instead. I have had the E+ fee refunded on every flight that I've had to cancel or change, and had it refunded when I've bought up to F. Granted, the sample size isn't huge, as I've only had to do this a few times outside of the 24 hour booking window.