Hi Tish,
You certainly have a lot of questions about sports and I am not sure if I am qualified to answer them for you, but hopefully somewhere in this message there will be at least one thing that will help you.
First of all a sport is a mutant. They pop up frequently in unstable plants and usually the plant keeps on sporting.
There is no way of telling if and when it will stop. You can try putting down a leaf and see if that matches the sport. If the bloom is a striiped or pinwheel blossom it may be a chimera which will not propagate the same way from a leaf, only from a sucker. Still if you put down a leaf and it remains true to the sport, then take a leaf from that plant and put it down too. If the plant remains true after 3 generations it will be stable, hopefully.
As for the plant with the two different blooms on it, more than likely it will change to one color and in my case the color I didn't care for. It's a crap shoot. Chimeras will need to be propagater from suckers or they will revert to something else.
Fred in NJ

Thanks fred, that helped some. So I've been interested in getting some chimera, keep losing the ones I really want on ebay cause I can't pay that much. But some growers/sellers state their chimera plant was grown from a bloom stalk...does that make that particular plant more likely to revert to something else because they didn't use a sucker? I wouldn't want to pay a chimera price for a plant that might become a regular violet, you know? Thanks, tish.

My understanding, albeit limited, is that bloom stalks or suckers will propagate true. I don't think one is less likely to revert or sport than the other.

I didn't even know you could propagate from a bloom stalk until a couple of weeks ago. This board is great for learning :)

I planted a leaf of Sora Pink Clouds (chimera) just to see what I get.

HI again,
Bloomstalks do not neccesarily bloom true. I have planted a number of chimera bloomstalks of The Alps and still haven't grown a plant that has the stripe.
Fred in NJ