They stopped making them in 2015, the closest thing is an Aunt Bessie thing in a plastic container for the microwave. It still has the same end result....burning the roof of your mouth off if you can't wait for it to cool before devouring it.
My grandson tells me apparently Heinz said on twatter they discontinued their entire sponge range! But like 3 odd years ago. But I have still been eating them since which is suspect.