About the Boston brewery. ( 3:30) These places usually reset every 7 days in game if it hasn't been cleared (that shows up on the map.) and 20 days in game if it has been cleared that and when you take a quest to clear somewhere out it auto resets.
Also on ammo, if you want to maximize input. Make sure to collect the weapons enemieshave as you will collect the ammo currently the gun After collecting you can drop it again and you won't lose anything.
Just so you know, picking up weapons enemies drop also let's you collect the ammo for that weapon. You can drop it right after if you want and you won't lose anything.