In the Chicken world, the rooster is King. The pecking order is in succession from there on down. If there are more roosters, they are subordinate to the Alpha rooster, and may be higher or lower in status than senior hens. The most senior hen may or may not be the rooster's favorite; she just has first rights for all treats, for preferred roosting spot, for walking anywhere all others must give way to her. The pecking order is also fluid and dynamic, in that it can change from within or without. If you add a chicken, the pecking order must be re-established. The new bird does not always end up at the bottom of the pecking order, either; she may fit somewhere in the middle high or low spots. But she most likely will never be equal to the senior hen. If their location is changed (moved to another property) or a new coop replaces the old or is added to the compound, the pecking order will need to be established again.
If an upstart roo challenges the Alpha and wins, the order is changed. If an upstart hen challenges the senior hen, or other hens with more status, she may very well move upward in status. Or not.