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>The Pokémon Company has put out a new note clarifying how the currently missing Mega Stones are going to be distributed. In the note, it explains that the Mega Stones will come through two means
>First, given as a present to players of Online Competitions, such as with the Mawilite and Beedrillite in the upcoming 2017 International Challenge February competition. Here, a limited amount of players will get the code ahead of a wait period of 1 to 2 months before all players get the code.
>Second is just through a code that will be given to all players through various events/online postings with no wait period
>The method will vary depending on the Mega Stone and they intend to go through these methods until Summer. As always, we'll bring full details on the Mega Stone distributions as they come.
This is from Serebii and to me it makes sense, no reason to screw people out of mega stones.