The first Hoenn Pokémon made available in Pokémon Go were released on October 20, 2017. 1905 days later, the platinum Hoenn medal is finally attainable as Kecleon is the 780th Pokémon species released in the game.
It appears that Kecleon will make its debut after Chespin Community Day.
Invisible Kecleon will appear rarely at PokeStops and prevent Trainers from spinning it. After it jumps off the disc, the Kecleon will appear on the map and can be encountered.
I just realized that Heroku is getting rid of their free dynos plan. I guess this is the end of this account then. Hopefully Kecleon will release sooner than later.