I have answered this before, it just was not that important. The early Church used whatever bread was available. As you have noted, the Armenians have always used unleavened bread.
It is unthinkable that if our Lord had used leavened bread during the Passover that the evangelists would have passed over (no pun intended) this in silence. To insist that leavened bread was used at the Last Supper is to anachronistically read back a latter usage.
YOUR STATEMENT IS NOT PROVEN & ASSUMES FACTS NOT IN EVIDENCE, Petrosius. "As you have noted, the Armenians have always used unleavened bread." Petrosius, I did NOT say the Armenians ALWAYS used azymes. Please do not put words in my mouth.