Google Play Edition devices are the Android based smartphones that are furnished with the manufacturer specific custom skins. In January 2015, Google puts an end on the sale of all GPE (Google Play Edition) based devices. Although, no statement was officially mentioned by the company, but no GPE based device were launched later that date.
Samsung Galaxy S4, one of the GPE based phone has popped up in the news as it has received the Android 5.1 update. Interestingly, Galaxy G4 is the only GPE device which has been garnered with this update. The Android 5.1, build LMY47O has been offered to this smartphone. The other interesting fact about this update is that the same update was rolled out in April this year. But it's a mystery as why it took 4 months to reach galaxy G4.
If you are owning one S4 and have recieved the update notification then its great. But if you have not received any update till yet, you can go to the source link (given below) and download the OTA ZIP file. In that case, you need to manually update the smart-hone to install the OS and experience Android Lollipop.