I think you can preemptively swipe (either as it's doing the Face ID auth, or beforehand) and then it will give you the passcode screen but Face ID is actually

I think you can preemptively swipe (either as it's doing the Face ID auth, or beforehand) and then it will give you the passcode screen but Face ID is actually still active on that screen, and when you complete it (either via Face ID or passcode entry) it will take you straight to the home screen.