I would never assume someone is upgrading unless it is explicitly stated.
To the OP: Your tank really isn't big enough for a full grown 24" fish. Something in the 15"-16" range would be fine, and that is the large majority of the CA/SA available in the hobby (pretty much most, other than Dovii and Umbee). Festae are amazing looking fish when full grown, but it takes awhile for the males to get to the size you're talking about (3 years or more).
I said earlier that he could have Dovii pair IF he was upgrading, it's up to him to tell us whether he will or not. I can't imagine someone specifically saying they want huge cichlids not being willing to upgrade for his fish if he has to.
and Buddha those Bocourti are the best I've ever seen, maybe you will inspire him to get some? I know If i see any now I'll be picking them up!