Got Sun, here infos:
The "League"
1. Seven Trials: Normal, Electric, Grass, Water, Fire, Ghost and Dragon | Ilima, Solphocles, Mallow, Lana, Kiawe, Wanda and JJ.
2. Four Kahunas: Fighting, Rock, Dark, Ground | Hala, Olivia, Hunter and Yasmin.
3. Four important trainers who are said to already have completed all the trials: Flying (Falkner's dad), Fairy (Valerie's best friend) , Bug (Viola and Alexia's brother) & Steel (Roark's mother and Byron's wife) | Wright, Alexander, Kim and Stella.
4. They give you Z-Stones.
5. Guzma gives you Poison Z-Stone and Lusamine gives you Psychic Z-Stone. Ice Z-Stone is post-game within exclusive Z-Stones.

The post-game
1. Z-Episode: Zinnia is back. You can visit Vermilion, Olivine, Lilycove, Canalave, Castelia and Coumarine. Must find Zygarde Cells.
2. Battle Tree: Only Red from protags. All champions. Blue, Silver, Wally, Barry, Bianca, Hugh and Shauna are back.
3. Building the League: Battle the "4 important trainers" and show them they are able to be Alola's E4. League is said to be finished in "Couple of months, just wait and see!".
4. See " UBs" on next post

Reboots
1. Cheers up! Second Hidden Ability confirmed! Poké-Pelago is how you obtain it.
2. Milotic is now Water/Fairy. It appears Lilligant also got reboot, dont have sure.
3. Solrock can have Drought, Lumineon Drizzle, Delcatty Technician, Gengar Infiltrator and... Levitate Aegislash.