30-45 days is optimal. 
21-30 days is enough.

more is funky/unpredictable.
less is not worth the effort. 

if you buy a whole chunk - u can cut steaks off along the way to see how it’s changing. 

u can always cut it up and freeze if u hit the stopping point. 

 Now I’m hungry. I’ve picked up ages steaks from Eataly before and I always loved the slightly odd smell.