Where was the Roman Army in AD408?

[Flavivs Aetivs]

It's a theory by Meghan McEvoy because there's no logical sense for Aetius to have been appointed as Palace Caretaker in 423 AD by Ioannes and then sent to fetch an army of Huns.

I don't remember the primary source that records he was. But it's always thought to have been a bureaucratic role, not a military one.