: My guess is that the crew of Gettys Justice were more focused on the task
: at hand, rather than identifying the individual ships which could
: obviously blow them away regardless of the class, type, or a ship that
: just so happens to be the same as your own. Cortana, who would be the only
: one to pick up on such a thing, might have spared them the freakiness of
: the situation so the Spartans would have a clear head. On the Covenant
: side, however, nothing indicates that they didn't have knowledge of the
: duplicate Ascendant Justice since their narrative is quite limited.

It's possible that the intended story is as straightforward as it sounds, that it's just that the Covenant AI was familiar because it was based off of a human AI because the Covenant are imitative not innovative (or based on Forerunner stuff she was already familiar with), but I like this idea, as it brings so much more complexity to the world and plays with time travel in interesting ways. I wish it was the intended story, even though it very well may not have been.