Maxstreel wrote:4 companies, 4 captains, 4 banner bearers?
You can't do that.
A formation is made up of companies. But a formation may only have 1 command company, wherein all the upgrades (captains, banners, musicians, taskmasters, goblin drums, Hasharin, etc.) are placed, and where the epic heroes must go if they join the formation. The command company is the first company purchased and the last company removed.
Note that cavalry works differently, since a cav company consists of only 2 models, but you still only get one command company. You have to designate which one it is, and so it can happen that epic heroes that join a cav formation may be removed before the command company is destroyed.