You never can be sure of what a seed will produce. Or, maybe you can if you're growing a pink obesum! But they can even change when they bloom the second time.
I'm trying to get seeds that do sort of come true, probably a five or ten year project, crossing double reds with different double reds, for example. So I can sell seeds that I can guarantee. In general, you now do get a white from a white, or a red from a red...