No, this is not an over and back violation.
One of the requirements needed to have this violation
is "team control". By definition, team control ends
with the try for goal, and no team control exists
during a rebound, even if touched, until a player
Therefore, in your example, team control is not
re-established until the ball is secured in the
backcourt. Team A would then have 10 seconds to get
the ball into the frontcourt, at which point the
restrictions for over and back would be back in force.