Well I tried again and now I qualify. I was thinking of getting S-Gear...now I guess I have more to think about. I've never been to impressed with my GR4 (Sonar version), but $49.99 is a very good price.
(EDIT)
I went to look again and the $49.99 upgrade price is a option now, (It wasn't yesterday) but underneath it says I have none of the qualifying products.