TXL-JFK is neither lay flat, nor will it be a fully upgraded 763. Only update so far is EC without power and pTV in Y. This route will be suspended at Sep., 2nd so don't expect any metal updates anymore (apart from a equip. change).
Well, I checked the flight status of JFK-TXL today, and it is listed as a 767-300ER with AVOD and lay flat seats...try it for yourself!