Thanks PE. The difference in the fully processed and blixed only strips are more than marginal. They are as clear as day. A user on another forum said that his processed Kodak RA4 paper was bright white in unexposed areas whereas mine isn't by any stretch of the imagination.
I did some research last night and came across a thread I had started then on the Colorstar in June 2006 I think I must have bought the Supra about then or maybe early the next year so it is more than 4 years old and has always been stored in my darkroom at ambient temp.