Astros game used stand question

[jwal23]

So I've only been to a handful of stros games over the past few years and i usually don't check the game used stand until after the game...but today is one of my very few and precious days off and we've decided to take our little girl to her first astros game and lucky for me King Felix is throwing today...I'm looking to pick up a King Felix strikeout ball (i'm sure there will be a few with the way the stros have been swinging it this year) and was wondering if anyone out there knows how quickly game used balls are sent to the booth and if they usually have thrown pitches from front line starters like Felix...thanks

[BamaHater]

This is a little late response but they start selling the game used balls in the middle of the 7th.