I don't know if this will help at all, but in February I traded in Hilton points for a 4 day hopper, they did not have the MYW tickets yet, but I was still able to use the hopper with no expiration date and 1 pass to pleasure island/water park. It was great for me, as I didn't have to spend any money and since I get these points through bookings I make at work, it was a great little bonus. I did read on the Hilton page that the new MYW tickets are non-expirable, here's the exact quote on their page:
Plus it also includes the No Expiration Option so that unused days never expire! It's a great way to maximize all the fun of a Walt Disney World® vacation.
So I don't think there would be much need to upgrade them. Some have said this is a waste of points, but for others it's a great offer. Hope this helps.