Talk:Nova/Prime/@comment-90.213.29.223-20150820212344/@comment-75.80.61.98-20150820233057

The letters correspond with the time intervals of Survival. First 5 Minutes is Rotation A, 10 is Rotation B, and 15 minutes is Rotation C. So every 15 minutes you have a chance of getting the corresponding part. So, for Chassis, you can get it during

15,30,45 minutes, so on and so on, same with the Systems.