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Yes, these are all much more satisfying answer! Of course Bulbapedia can be wrong and has been wrong before, but that doesn't mean I should assume it to be wrong, I wanted to be sure.
Encore lasting 8 turns including the turn it is used makes sense if it is programmed that way, but I'm glad to...
I was playing gen 4 random battles and had Encore used against me. However, this lasted MORE than the maximum of 7 turns.
After turn 8 my Pokemon fainted, so I don't know if it would have worn off then.
Bulbapedia, Pokemondb, Serebii and such all list the move as 3 to 7 turns since Pokemon...