>>>>and implies that Iona did not defect.
>>>
>>>And yet, if she didn't defect, why was she found alone? No
>>>black-marketeer would have passed up the chance to put multiple Fleet
>>>of Fog ships in the inventory.
>>
>>"Extended deep-cover assignment" á la Léonne?
>
>In truth, we know very little about Iona's circumstances. All we can
>know for sure is either the ship or the Mental Model was destroyed and
>the Union Core preserved. We don't even know which form she was in
>when it happened, or when. There's a 300 year gap, and it could have
>happened at any time.

There is one piece that nobody appears to have picked up on:

Iona glanced at Corwin, received a nod, and replied, "Long-range submarine I-401."
"Four-oh-one! Huh. I thought you were scrapped," Tenryū said.

There-in lies an interesting possibility. Supposed the original shell of I-401 -was- scrapped, but the core was not? Placed back in stasis, left in a particular location, or whatever. That could explain why Miss James only had the single Core, and why it required a bit of work to reactivate. Also, if she was scrapped, Iona would then likely have been the -least- well-informed member of the group in terms of what happened after the war.