We know from Spartan ops that the UNSC found at least one composed human AI on Requiem after the Didacts attack on Earth. Now this composed human must have been transmitted from the Didacts ship to Requiem. Facing her own distruction could Cortana have transmitted herself to Requiem in the same way? The Storm Covenant had access to composed Promethean knights, and could have recieved Cortana’s AI. This theory would place Cortana in proximity to Halsey, aiding in her ultimate presevation.
My theory is that since the Composer can also turn digital intelligence into biological life, then Cortana will somehow come back as a human. This would be a very interesting and hard to pull of story.
Cortana as human?
Her and chief?
Chief teabaggin her?
What?
As of now , we don’t really know if Cortana is 100% dead or if she survived in some way . But what I know is that there’s a 29+ pages thread that is all about Cortana and her role in Halo 4 !
https://forums.halowaypoint.com/yaf_postst137119_Cortana-s-Role-in-Halo-4--In-Depth---Spoilers.aspx
If you have a theory , an idea or whatever related to how she could have survive after Halo 4 . You should check this thread out ! 
If she did, which is doubtful, then it was temporary. With what little power she lad left she saved Chief. I know there is that massive thread talking about how she might’ve survived, but to me it is about as relevant as the people who claim Jorge could be alive despite being confirmed dead multiple times. The Epilogue’s description states she died, that is good enough for me.
Jen Taylor got to eat
> Jen Taylor got to eat
And she will… As Halsey she will continue to eat. 