I would never waste this on a mythical unless it was Darkrai when Dark Void is finally released. By then I’ll probably have a hundo anyway.
In subreddit r/TheSilphRoad
In a post titled:
New datamines show you will be able to turn a zero to a hero with Hyper Training, though the process will take an entire year. Rejoice everyone who had kept their shiny mythicals around!!!!