Usually their front-end callsigns have two numeric characters ("ALVA 41") and the battlestaff callwords don't (which is why they're technically callwords, not callsigns), so based on the little info you shared, I don't think it is correct to assume that "Alpha Four" was actually callsign "ALVA 4." Let's just hope "Alpha 4" wasn't their maintenance status (cuz it'd basically mean they crashed & burned).