Man, that slot machine line hits home... variable rates are a trap.

But you changed two things at once, the method and probably your grind and brew temp, so how do you know it was the Aeropress and not just dialing in the Ethiopian better? Three weeks and twelve cups each is a tiny sample too. I'd bet a good pour over with the right grind would smack that Aeropress around.

Trust the dough over the clock, seriously. I've had loaves take 18 hours when my place dipped to 55 degrees, and they came out even better than the quick ones. Once you accept that temp controls everything, you stop stressing and just work with whatever schedule the dough wants.