
Originally Posted by
meme_engine
While I can't answer for the OP, I have had instances where ships that have surrendered (in some cases were even surrendered and sinking) have sailed away under their original flag after the battle. It certainly seems that if the ships appear in the battle as reinforcements, they cannot be captured if they surrender during the battle.
So, if you enjoy sea battles you let them go and have another fight. If not, it might be worth sinking them when they're a sitting target.