Zodiac and Late Roman Army Organisation

[Flavivs Aetivs]

one can’t see those Palatina units as ‘auxiliaries’ anymore. They were, with the Scholae units, the core of the Imperial field armies, after all.

But surely Silvanus was in command of just such an imperial field army at the time? [..]The latin for Silvanus' command is octo auxiliarium milibus - not very helpful!

Yes, he commanded a field army, and I expect him to have commanded several comitatenses and even palatina units. But all of them?

It may be possible, depending on how well stocked the Limitanei garrisons were at that time. I don't have access to (Ammianus, I think) right now, so I can't check what they say about the state of the army under silvanius. But late on, Stilicho commanded the Entire Italian field army to fight radagasius, and Aetius the entire Gallic army and palantine troops to fight the goths, franks, burgindians in the 430s and the Huns in 451, but both of these armies were consdierably smaller than they would have been around the time of Silvanius and Julian.

So it's possible, but not plausible.