I have been on royal forums talking about this and there are lots of theories floating around. I’m very surprised that there is still no law suit from William and Kate and it looks like there isn’t going to be. That makes me suspicious.
I do wonder if this was something that William and Kate arranged. Perhaps a friend took those photos and William instructed that friend to hold on to the photos and only publish them when William called him. But I guess we’ll never know the full story.