It's my understanding (and goodness knows I've been wrong a LOT) that Blue/Black/Splash is all the same color gene, so you can get all three in a single hatch. Splash is a blue bird with splashes of dark color.
Jubilee and spangled/mottled have splashes of white and are a different color gene entirely.
You can, but only if you have the right combinations. Blue birds bred to blue birds will produce blue, black, and splash offspring. Blue bred to splash will produce only blue and splash. Blue bred to black will produce only blue and black. Splash bred to splash will produce only splash, and black bred to black will produce only black.