In my opinion it definitely does expire. I was using some cypionate that expired around 1/19/2019 about 3 months ago and I realized I was having trouble getting erections.
When I took my regular small dose of AI arimidex with a dropper about 1/80 of a mg which usually just kept me in balance it was really crashing my estrogen which it would never do.
I was so perplexed and started adding additional dosages to no avail. My cypionate was kept in a laptop bag in a truck so it was subject to frequent temperature swings which probably reduced it’s lifespan.
But from my experience I wouldn’t use anything that has gone past 6 months expiration date even if it was kept in a cool dry place. Now that i’m on non expired T I can feel everything slowly coming back, but it’s a real shot in the ass to crawl back and dial yourself in after using non effective test.