After upgrade to iOS11, Photo uploads files to icloud even though the phone is on mobile network

Before iOS11, the photo app does not upload newly snapped photo to icloud if the phone is still on a mobile app. It will usually say, to the effect, "Upload paused while on mobile network" at the bottom of the 'Photos' section.

However since I upgraded to iOS 11, the photo will upload regardless the type of network connection. It killed my mobile data! On one weekend, 1 Gb of data was sucked away because of the upload.

Has anyone else encountered this issue? If so, is there a solution?

This is the 'Mobile Data' settings of photo app:

This is an ios11 feature. (I think it is actually a bug because I did not observe this kind of behaviour before)

I find that I put the phone in 'Low Power' mode, the Photo will not attempt to upload the photo automatically.

Now I will turn it on before I take any photo while on mobile network.