Generation 4, will be added in the next version. ♂️
This does not mean that it is going to leave now, but it will be added to the new APK, in which Niantic is working. Maybe, the arrival is scheduled for Halloween or the Fall Event (after) aside, the loading screen is modified.
I do not want to create hype … but between the end of the month of October or mid-November, the most anticipated of this year is coming, without commenting the player against player in December 2018.
• badge_pokedex_entries_gen4_title: " Sinnoh "
Source: Community GO News