FWIW Early Adopter unlocked successfully for me after getting the season pass in the recent sale. Seems like it's only glitched for a few.
Similar thing happened with the T-Mobile thing from MCLA, popped for dozens of people I was playing with but would never go off for one guy despite multiple efforts.
Games With Gold for dummies
Mutual assistance for the following games' achievements:
Need For Speed: Hot Pursuit (MP including the DLC),
Gears Of War 1 (Hardcore Campaign, Dom run one of them),
Battleblock Theater (Open for trading, 3 out of 10! Co-op, etc.),
Might & Magic: A Clash Of Heroes (MP stuff),