First you must tell what Campaign you have started, April Campaign or July Campaign.
If you started April campaign you must search in C:\Games\Civil War II\CW2\Events
for 1861 April Campaign.sct
If you started July campaign you must search in C:\Games\Civil War II\CW2\Events
for 1861 July Campaign.sct
Backup the file as you will need backup file if you wish to start new game.
Open the file in notepad, and paste this text at the end of the file:
SelectFaction = CSA
SelectRegion = $Richmond_VA
StartEvent = evt_nam_CSA_ MODCorpFormation|1|0|NULL|NULL|$Richmond_VA|NULL
Conditions
FixedDate = 1862/03/01
Actions
SetFormedCmdMax = 9999;9999
EndEvent
SelectFaction = USA
SelectRegion = $Prince_George_MD
SelectFaction = USA
SelectRegion = $Prince_George_MD
StartEvent = evt_nam_USA_MODCorpFormation|1|0|NULL|NULL|$Prince_George_MD|NULL
Conditions
FixedDate = 1862/03/01
Actions
SetFormedCmdMax = 9999;9999
EndEvent
I have bold-ed the date for corps forming, modify it so it fires on your next turn (if you are let's say in Late April,1863 you would need to change the date to 1863/05/01)