I think my faction has been pending expansion for four days. How long does this normally take to roll into the expansion state? Or, is there something I should be doing while I'm pending expansion to assist?
Pending lasts 5 days, nothing you can do to assist.
Expansion itself should be 5 days, expand on the 6th. This can however be cut short if intervened by something else, like War. So if during the pending period, say day 3 you maneuver youre faction to start a War, you can force the curtailing of Expansion, but still expand. Ive had it happen and expanded after 1 day of Expansion state.