Actually I think the last few days recommendation is off by quite a bit. Most boutique roasters I know about typically recommend to use the beans within 2 month

Actually I think the last few days recommendation is off by quite a bit. Most boutique roasters I know about typically recommend to use the beans within 2 month after roasting and some even recommend to not use the before 1 or two weeks after roasting . A different test would be the grinding one. I am very sure I can taste the difference between fresh ground and ground a day or two ago coffee (for espresso however). I would be interested what you get for that experiment.