The dates are:
Creating Divisions: 1861-Oct-01
Creating Corps: 1862-Mar-01
To create a division with a leader:
- It must be the 1st of October, 1861 or later.
- The leader cannot be the commander of an army, a corp, another division--of course--, nor combined with a brigade.
- The leader must be activated--has the light beige envelope at the top left corner of his unit's picture-frame, and on the Unit Display when clicked.
- If the leader meets these requirements, click on the leader and then on the Enable Division Command button to the left of the Unit Display in the Special Orders section in the Tab with the Tent.
- You must now maintain at least one unit in your newly formed division. If you leave a Division Commander alone without any units and execute a turn, the division will be disbanded.
- To add units to a division left-click on the division and then cntl-left-click on the unit(s) you wish to add to the division and either click the Combine-Units Special-Orders button or press <cntl><c>
- To break-down a division to it's constituent units, left-click on the division then click on the Split-Unit button or press <cnlt><d>.
To create a corp with a leader:
- It must be the 1st of March, 1862 or later.
- The leader must have obtained the rank of Maj. Gen. or greater.
- The leader cannot be the commander of an army, or another corp, nor combined with a brigade.
- The leader is NOT required to be activated, but if Hardened-Activation rules are in affect, the leader must be unlocked.
- The leader must be within the Command Radius of the Army Commander/HQ.
- If the leader meets these requirements, click on the leader and then on the Attach Corp to Army button.
- Your Corp status is maintained as long as you wish, regardless of if the corp is empty or not or within or outside the command radius of any army HQ or not, with one exception:If you transport a corp with Real-Transports™, either riverine or oceanic, the corp with be disbanded
leure:.
Ergo, if you want to invade with a corp, your invasion coastal/river region must be within the command radius of an army HQ. As soon as you drag-n-drop the corp commander from the transports to plot his move, you can recreate his corp, but only if he is within the command radius of an army HQ.
The army HQ may be on a transport to facilitate this.

apy: Questions?