Yes relinquished teams (from when people take over a lower level team) go onto the list of teams seeking managers directly, and teams that have been abandoned (not logged in to) wind up also on that list after a couple seasons.

If it was a nice team when managed it can still be annoying to face unmanaged with players out of position (oop) Expect a victory but plan like it's a real team. The game will place whatever bench players are available (and if assigned in subs the correct spot) in the empty places. Often the second half of an abandoned team's last season you wind up getting a forfeit score (3-0)if they haven't got enough bodies to fill the pitch.