i think to remember, hearing that one can, "dry them out", and maybe this increases the shelf life.
mine, got bought, a bit wet and i stored them a bit wet, in the fridge, not the freezer.
you as well hint that at times you loose focus, with the grains, an issue, i have as well, as i don't want to be slave to the kefir grains.
meaning i would be very interested to hear about how to take a break, from brewing, and how to store them...