Yup - JFK can fill up very quickly. 48 hours before my flight, it was F5 then day of departure it became F2 and then we departed full 6/6 (I saw someone use an upgrade voucher at check-in.) Didn't notice or care about the other passengers seated - that's how private the A aisle is and there was plenty of Krug and food to go around, I was able to get everything I wanted to eat.
Enjoy!
