Anthony. I belive that Auston's Battery, is actually Trigg's Battery that was was part of Shoups Artillery Battalion. Trigg drops out of sight after Shiloh and Auston shows up as the commander. See the post below from Bryan Howerton.

Damon -- Trigg/Auston BatteriesBy:Bryan Howerton
Date: 2/15/2013, 12:12 pm
Damon, I've been rummaging through my CW stuff for my old research notes on Trigg's and Auston's batteries, but so far I haven't found the right box. However, I just remembered some interesting information from those notes. As you know, the muster rolls of Capt. Putnam Darden's Mississippi Battery (Jefferson Horse Artillery) state that in July 1862 (I believe) several men were transferred in from Auston's Arkansas Battery. I recall researching those men, and noted that some of the men enlisted in Alabama in early 1862, so I checked the Alabama pension records and found a couple of men who made the move to Darden's Battery, but stated that they were actually members of Trigg's Arkansas Battery. So there is a connection between Trigg's and Auston's batteries. If I can ever dig that research out, I'll send you what I have, assuming I don't get sidetracked with new stuff, which happens with great regularity with me.