Forum adverts like this one are shown to any user who is not logged in. Join us by filling out a tiny 3 field form and you will get your own, free, dakka user account which gives a good range of benefits to you: No adverts like this in the forums anymore. Times and dates in your local timezone. Full tracking of what you have read so you can skip to your first unread post, easily see what has changed since you last logged in, and easily see what is new at a glance. Email notifications for threads you want to watch closely. Being a part of the oldest wargaming community on the net. If you are already a member then feel free to login now.

Can a character join a unit that has scouted onto the board?

This would mean my sorceress (on foot) can start the battle with shades that are 13" away from the enemy, and out of their charge arc

No, as you place scouts after you place characters.

The character COULD join them, just not during deployment. The character would have to join the unit during a Movement phase.

Thanks

Only characters that have the Scout special rule can join a scouting unit. Assassins are the only one in the DE book that can.