Use more than one account on a platform

Connect a second account and choose which accounts each post goes to.

Press + Add on a platform's card to connect another account. A platform with more than one account shows a stack of cards: the front card shows that account's details and the strip above it lists the other handles. Click a strip to bring that account forward.

In Create post you tick which accounts each post goes to. Manage opens the account in front, so you always know which one you are changing.