Very interesting. You stay out of a lot of trouble by taking that literal-grammatical approach.
I don't think the ECF would have called it that. Irenaeus eschatological beliefs, for instance, were taught him by Polycarp, who in turn was taught by the apostle John...who wrote the Revelation. His strong Rev. 20 based belief in a future earthly millennium would thus have come down to him (via Polycarp) from John himself. His futurist post-trib premillennialism, he considered apostolic.
There is not the slightest hint in his writings that he had ever heard of any such thing as Preterism, Amillennialism, or Postmillennialism...reason being it hadn't been invented yet. This stuff Freneau pushes around here, certainly not.