Why does Google play services use way more battery when I turn on my stamina mode...

[AC Question]

After the new 6.0.1 update, is it possible to use the stamina mode again on my Sony Z5 compact. Although I thought this would be a nice improvement, is there a big downside... Google play services normally uses less than 1% of the battery, but when in turn on my stamina mode it rises to about 15% of total battery use. This counters more or less the gain I could have from the stamina mode. The only way to get the power use back to about 1% is to stop the background data use of the google play service. The real problem is therefore that google play services is very busy with something in the background while stamina mode is on. If I turn the background data of Google play service off I do not receive any more push messages from my apps even with the settings that they should not be optimized for battery use. With other words, I will only see my new apps when I unlock my phone and open Whatssapp.
Does anybody how to get the power use of Google play services back to normal in stamina mode, without losing the push messages from apps like FB, snapchat and whatsapp?

Thank you