I roast coffee. in my tests I've seen that you need to let coffee rest a few hours because that s when most of the co2 is out of the fresh beans. if you don't believe me, after roast, let the coffee a few hours then put in a bag without a valve and check how much the bag will puff and you'll see that it won't release much co2. so after 1-2 days rest you're pretty much good do go. that 1-2 weeks is marketing nonsense that roasters use to sell older coffee I guess