I went in for gastric bypass surgery in December last year and have since dropped 32kg. Now my weight is stable at between 80-82kg with BF @ about 22% and muscle mass @ 39kg. I've been doing a lot of cycling and can easily do 20 km/day for 6 days straight. At this point I'm looking at extending...
Do a search for "shelf life" and it'll provide you with all the information you need.
Summary: SARMs will hold for a couple of years as long as they've been kept in a cool dark place.