So if I understand it right, Shield Boost is both repair and reinforcement, yes?
Let's say the CA, which starts with 24 shields, has taken a few hits and is at 18 left. It uses Shield Boost and roll box-cars on 2d6. So, for this turn only its shields are at (18+12) 30 points, and as long as it has not taken more than 6 hits on shields during this turn, they're back to a full 24 for the next turn and there after (until the ship is hit again).
Is that correct???
Or does Shield Boost only take them up to the original amount, and the extra are lost?