So I've been messing around with fleet builders and Ive come across something. When you pair General Rieekan {saving your ships till the end of the round) and having reinforced blast doors ( discarding 3 damaged cards) does that save your ship till the next round?

No. The ship is already dead so you cannot repair either by command, token or upgrade card.

A ship that was destroyed and not removed from the play area was still destroyed, no matter how many damage cards you remove from it.

So you'll still have to pick it up.