They finally solved those problems, and I received some of the previously unavailable colors over a year ago, so it seems to have been fixed. For those who haven't heard the story, here is what the new owners had to say about the problem, on Oct 3, 2015, in a response to my emailed questions:
"We are currently having issues putting some colors in spray cans. One of the pigments is causing a chemical reaction with the aerosol. This is causing the paint to foam out of the can as soon as we put it in. there are 2 of these colors on your order SC II UP Yellow 2022 and SC II BN Green 2038. We are currently waiting on a new brand of pigment that will hopefully correct this issue."
I called them on Dec 8, 2015, and they said the reaction was "violent" - it blew the tops off several cans and made a horrible mess. Apparently, Scalecoat, like many paint companies, buys the actual pigments from outside suppliers, and the supplier changed the formula without telling anyone. Something in the new pigment reacted badly with something in the spray cans. The actual solvents seem to be the same for spray and bottle, so my guess (no firm data) is that it was the propellent.