I'm assuming you let the seasons screen fade away. When that screen is up, the backpacker can still move around. In any case, best thing to do would be to check your shifted starting PID frame. Simply engage battle with Terrakion once you gain control of your character (best not to use your Sync when doing this), capture it and compare the result, and then you'll be able to determine how many advancements you need. If your ear is attuned, you can pick up the sequence of Chatot cries/pitches to see what frame you're on.