Yes, they are producing many yellows, purples and quite a few others.
Pink and Red shades are the most common.
If really want a particular color/plant, you are best to purchase a grafted plant to get that exact flower. Seed will be a luck of the draw, sorta speak.
Many of the Yellows will fade as flower ages and there are a few with a more true yellow.
Rick

Thanks for the information

I really love the yellow, which stay yellow as they age?