any chance you could maybe give us some more details so we can figure out what stopped the damage?
Are you sure all 40 squads of bombers were alive and hadn't just been more or less shot down by the time the capitalship had 266 hull left?
If your 40 squads of bombers were definitely all alive are you sure they were actually attacking? A large presence of Halcyon Carriers or Kortuls could potentially keep them from actually firing or a single Akkan using Armistice would stop the battle entirely.
how much shield did the target have? If it's advent I could very well see them having at that point just managed to reduce your damage output low enough(after kills some of your squads of bombers) to out-heal your damage.
Honestly nothing like that happens without a reason- we'd be eharing about it all day on the forums if it did. Which leads me to one conclusion: you're overlooking some ability or synergy or aspect of the battle. Ships don't just stop- taking damage for absolutely no reason.
And if they have it's a very unusual bug(literally have never heard anyone else report this), which seems to be a childish reason to quit a game.