OK, since the documentation is lacking this point, I gotta ask here...
wikipedia says
Terminal 2 has 7 jetway equipped gates: 20-22, 26-29 and 17 stands for Delta Connection carriers: 23A-H, 23J, 25K-N, 25P-S
What are the equivalents in your JFK scenery? I couldn't figure it out and I've really tried a lot of gates/parking.
Best regards.