I'd always thought Alans were strictly mercenary, but looking at the Clan Berserk unit tool makes me wonder. It says "Byzantine, Golden Horde, Russian and Turkish" factions can build them (at least, I think that's what it means) in any period, but that "++Georgia,Khazar++" are "required".

I'm playing the Byz for the first time, and started with a unit of Alans. I've only 3 of them left, so I'd like to reinforce them. Is there any way I can?