Let's knock out 2 TL designations & sketch it out, roughly:
(Pre-Stellar) TL 7 (current)
(Pre-Stellar) TL 8: Fusion, grav tech
(Early Stellar) TL 9: 1st half J-1, crystal iron, Thrust Plates, 2nd half J-2
(Average Stellar) TL 10: J-3, terraforming
(Average Stellar) TL 11: J-4, Cloning body parts, battle dress
(Average Stellar) TL 12: J-5, man-portable fusion weap., Flying cities
(High Stellar) TL 13: J-6, anagathics, early black globes, prototype anti-matter power.