Sadly, the new DLC will not be included with the season pass that ended with the release of the Tiny Tina DLC
Source: New Borderlands 2 DLC, Level Cap Increase Coming This Fall - IGNDuring a panel at PAX Australia today, Gearbox confirmed that the level cap forBorderlands 2 will be raised by 11 levels to 72 this fall, plus new missions and raid bosses will be coming as additional DLC packs.The level cap increase will come along with the Ultimate Vault Hunter Upgrade Pack 2: Digistruct Peak Challenge, which will be released for $5.00 before the end of October. The Digistruct Peak Challenge is a new map where Patricia Tannis will let players fight high-level enemies (which they can "over level" to create an "impossible" challenge) to earn new loot. An upcoming free update will also add additional backpack, ammo and bank slots.
Gearbox will also release multiple “Headhunter” packs offering new missions and unique themed boss fights. The first mission will be T.K. Baha’s Bloody Harvest, bringing back the character last seen in Borderlands 1’s Zombie Island of Dr. Ned DLC. Zombie T.K. Baha will send players to fight Jaques O’Lantern, a giant pumpkin boss who will give new character customizations as a reward for being beaten. Multiple headhunter packs are coming in the future (at least two and possibly three), but no specific pricing or release dates have been announced.
All new DLC is separate from the Borderlands 2 Season Pass, which concluded last month with the release of Tiny Tina’s Assault on Dragon Keep.
Gearbox will also be releasing more character heads and skins later this year, which will arrive "within two or three weeks," including a set of themed heads related to Tiny Tina's Assault on Dragon Keep.
Today’s news confirms a tease from Gearbox head Randy Pitchford earlier this month, and Gearbox promises that more details will be revealed in the coming weeks. Gearbox will host its next Community Day for fans on September 14th (and will stream it online), so expect more details by then.