1 Sept 2023
Counters on Restless Bivouac remain on it when it stops being a creature. If it becomes a creature later, they'll apply to it.
1 Sept 2023
If this becomes a creature but you haven't controlled it continuously since your most recent turn began, you won't be able to activate its mana ability or attack with it that turn.
1 Sept 2023
If this becomes a creature because of an effect other than its own ability, its last ability will still trigger whenever it attacks.