These were My snow peas are Oregon Sugar Pod with no II suffix. My sugar snaps are Little Marvel.
I didn't see any signs of disease except one of my snow pea plants did yellow and the pods it produced had little bumps on them.
I think the snow peas shut down when they intended to. I got over 3 quarts out of a 4' x 4' plot. The sugar snaps, I think they really need to be planted 2-3 weeks earlier than the snow peas since you have to wait for the pods to set AND mature. It's a learning experience.
That's a great article. Based on that, I might be tempted to grow both Oregon Sugar Pod and Mammoth since the Oregon Sugar Pods are definitely smaller than I'm used to. I would plant the Mammoth on the 1st of November so they are producing mid-January to mid-February. Still, I really like the snow peas and they serve just about the same purpose. I might grow a shelling pea like Thomas Laxton or Green Arrow as I love English peas. And I intend to experiment with vining varieties for extended harvest.