Blue-duncan says the last days started with Adam. That could be, but none of the OT authors (Isaiah 2:2, Jeremiah 23:20 and 49:39, Eze 38:16, Hosea 3:5, Amos 4:2, Micah 4:1, and Joel 2:82-83) write about the last days as anytyhing but future, and not a "developing" event.
It is only in the New Testament that one begins to find references to "these last days" in the present (Heb 1:2 and James 5:3), which you cite. However, 2 Timothy and 2 Peter do not share that view but rather continue to speak of the last days as a future event:
"Know this first of all, that in the last days mockers will come with their mocking, following after their own lusts." [2 Pet 3:3]
Going back through the posts, I don't see where b-d stated that it began at the times of Adam. I believe that b-d was refering to the "last days" as the time from Pentecost to now.
However, 2 Timothy and 2 Peter do not share that view but rather continue to speak of the last days as a future event: "But realize this, that in the last days difficult times will come." [2 Tim 3:1]
Of course they speak of future events. They are future things in these last days