When do you need a third corps

[carlc]

So, I am just now up to the Peninsula Campaign, so still in 1862. So far, I have not see a time when a third corps would even be allowed on the battlefield. I am asking this in context of the career points with army organization. I know that ultimately, or I assume ultimately, I would want more troops on the field...but when should I start that development. I am more eager to get my first corps into two stars for each division (3 divisions, 4 brigades...playing Union).

[Half life Expert]

Trust me, you will need a 3rd Corps down the line. At least at Antietam for sure you will need them. Some battles will require at least 3 corps. Get a 4th corps as well at some point if you can.

The further into the war yu go, the larger and bloodier the battles will be. You WILL need more brigades and gun batteries.

[Malkor2]

I would say at Antietam. You don't need a full third corps there but having something between 5-10 Brigades in a 3rd Corps at Antietam should be enough.

[Kristoph42]

I would say 2nd Bull Run, is the first battle that enables you to have a third corps on the field. When you get to that battle you should have a few units in your new thrid corps. All the grand battles after that you can deploy your thrid corps, except for Chickamauga. By the time you get to Antietam you might want to start thinking about putting in a fourth corps,