Hey y'all. This isn't any sort of a news post. But instead, I'll be going over Pokemon Sun and Moon's pre-release season and gathering when, what and where information was announced. If you're curious about X&Y's pre-release schedule, please see HERE. Without further ado, let's get on with it! 

February 10
Magearna
 

February 26
Game Name + Logos
Release Month
Concept Art of various titbits (The Region, Lillie, Pikipek)
 

April 12
Magearna's typing revealed
 

May 10
Region Name
Region Map (for Melemele Island only)
Box Art
First Look at Region
Kukui & Hala revealed
First Look at Mom & Hau
Starters
Legendaries
Character Customization
Release Date

May 13
Rockruff shown
 

June 2
Full Regional Map
More info on Solgaleo & Lunala
More info on Kukui & Hau
Lillie revealed
Rotom Pokedex
QR Scanner + QR Codes
 

June 11
More info on Rockruff
Komala
Zygarde Formes
Magearna Event
 

June 14
Move Selection Screen Changes
Stat Changes Screen
Pokedex Screen
Pikipek
Yungoos
Grubbin
Battle Royale Mode
 

June 15
Sun & Moon 3DS Revealed

June 30
Tapu Koko
Charjabug
Vikavolt
Drampa
Cutiefly
Togedemaru
Bruxish
 

July 7
Salandit
 

July 12
Mimikyu
Bewear

July 13
First Look at Z-Moves
First Look at Pokeride
Pokemon Refresh
 

July 19
Wimpod
Bounsweet
Comfey
Mudsdale
Pokemon Global Link - Custom Competitions
Hyper Training
 

August 1
Alola Forms Revealed
Alolan Sandshrew
Alolan Sandslash
Alolan Vulpix
Alolan Ninetales
Alolan Exeggutor
Oricorio
Gumshoos
Lurantis
Minior
Island Challenge
Trial Captains
Mallow, Kiawe, Lana and Sophocles shown
Totem Pokemon
SOS Allies
Island Kahunas
More info on Pokeride
More info on Z-Moves
 

August 9
Sandygast
Palossand
Stufful
Wishiwashi
Alolan Meowth
Alolan Marowak
Team Skull, Guzma & Plumeria revealed
 

August 10
Pyukumuku
 

August 11
Alolan Raichu
Morelull
 

August 18
Turtonator
 

August 19
Crabrawler
 

September 1
Alolan Rattata
Snorlium-Z
Pre-Order Bonus
Munchlax Event
 

September 6
Type:Null
Jangmo-o
Alolan Raticate
Day/Night Mechanic Changes
Aether Foundation revealed
Lusamine, Faba, Wicke and Gladion shown
Zygarde Cells + Cube
Dexio & Sina revealed
Pokefinder
Ultra Beasts announced
Nihilego
 

September 8
Samson Oak revealed
 

September 12
Lycanroc (Both formes)
Buzzwole
Pheromosa
 

September 20
Oranguru
Passimian
Pikanium-Z
Eevium-Z
Pokemon Bank Updates
 

October 4
Dartrix
Torracat
Brionne
Festival Plaza
Poke-Pelago
Ash-Greninja
VGC Rules
QR Rental Teams
Global Missions
 

October 7
Ilima shown
 

October 12
Alolan Grimer
Hakamo-o
Kommo-o
Silvally
 

October 14
Tsareena
Ribombee
Alolan Muk
Akala Island revealed
Olivia revealed
 

October 17
Mareanie
 

October 18
Sun & Moon Demo Released
Alolan Dugtrio
 

October 20
Alolan Persian
 

October 23
Shaking Grass mechanic
Info on Trials & Z-Crystal Rewards
 

October 27
Decidueye
Primarina
Incineroar
Tapu Lele
Tapu Bulu
Tapu Fini
Cosmog
Battle Tree
Cynthia and Wally shown
Red & Blue re-designs
Communication Features
 

November 11
Kartana
Celesteela
Necrozma
Guzzlord
Signature Z-Crystals for the Starter Pokemon
 

November 14
Xurkitree
Z-Status Moves

November 18
Sun & Moon Released Worldwide