To all and Phil,
I have bought the yeast at SAM's for years. I keep it in the freezer and get
it out just before I need it. Mine has kept for over a year, probably two at
times if I don't use it up fast enough. I have yet to have it not work for
me. I open one of those packages and pour it into a freezer zip lock or put
the opened package into a freezer zip lock bag.
I bake from scratch and don't have an ABM but it has worked fine for me.
Don't feel you have wasted your effort in buying the yeast in quantity. I
keep it in my freezer that is attached to my refrigerator, by the way.