Maree, my Bl. Golden Glory has bloomed anywhere from almost pink a few years back, to butterscotch orange this year. I have no good reason why, but I sort of enjoy the surprise from year to year.
I agree with the temp and light possibilities as well as the Richard Mueller theory Gin described. I only have one catt hybrid in my entire collection and it is a Richard Mueller cross and when the flowers open they are a dark rich gold and as they get older become a nice pale yellow.