Rereading Parvaneh Pourshariati's "Decline and Fall of the Sasanian Empire" I note that Armenians are involved with Persian armies until at least 643 CE - with Tabari being her main source on this. The latest certain mention is in 643 CE an army made up of an Armenian contingent under Khusrow Shenum/Varaztirot Bagratuni, a Daylamite contingent and a Persian army from Azerbaijan fought, and lost to, the Arabs.
Suggest the Late Sasanid list be allowed an Armenian ally.
Also probably a good case for an optional internal Persian ally general (or two) as cooperation at this period was not always good.
For the interested the book mentioned - https://www.amazon.co.uk/Decline-Fall-Sasanian-Empire-Sasanian-Parthian-ebook/dp/B07PBR6GD1/ref=dp_kinw_strp_1
Just bought it :D ;D
Not the easiest book to read but extremely interesting IMO.
I need to pick my way through the post-Sasanid Tabaristan section sometime to see if there is a possible new list there :D
Just reading 'The Sassanians' by Kaveh Farrokh at the moment
Not a big fan of his work, but it is useful in places.