Pokémon GO Gen 2 patch on previous Pokémon games such as Silver, Crystal and Gold caused changes to the usual spawns. Players experienced day and night spawn in future generations. As a result, it brought a brand new challenge in capturing these particular Pokémon in a certain time to fill out the PokeDex. Meanwhile, several trainers are curious if Niantic implements this system to Pokémon GO now that they already launched the Gen 2 patch to the game.
According to Otakukart, some trainers agree with others as they noticed that the Oddish nests are transformed into Leydeba as dusk hits. However, this could just be an accident as players are suitably visiting particular spots and revisiting every 30 minutes to one hour.
Apparently, Niantic originally does have a plan regarding the day and night spawns when introducing the game to the public. It is to attract the eyes of the game's investors. As of this writing, it appears that some spawns change every hour while some changes between spawns every 30 minutes. It would make more sense than the day/night spawns for this type of game.
On the other hand, the Pokémon GO community is expected to clarify this topic, as the game will be adding new features and Pokémon soon. As of now, players are recommended to anticipate the upcoming three major updates of the game throughout the year.
Though Niantic has not yet released any details as to what is coming, however, fans are heavily suspecting that the upcoming patches would include Trading, PvP and Legendary Pokémon. Additionally, Niantic CEO John Hanke said that they would be doing some re-work on Pokémon GO's current gym system. Hanke said that they will make the gyms more dynamic and challenging since several trainers noticed that it has become dull and flat.
Pokémon GO is now available on Android and iOS devices.