You may already have noticed various changed in Pokemon Go due to the recent update. This page notes how to transfer Pokemon now. If you want to know the details of the update, see the link below noting examined changes.
News: Details of update on July 31
Favorite start function is used to keep false transfer from happening. The link below shows hot to use favorite start.
What is favorite star in Pokemon Go?
Dratini nests and spawn locations
Charmander nests and spawn locations
Drowzee nests and spawn locations
How to use 'Poke Assistant' for team building
Gastly nests and spawn locations