Apple Music Cellular Data Glitch / Lossless

Since the launch of Apple Music lossless, I have activated lossless audio for WiFi streaming and downloads only, with cellular data set to high efficiency due to my limited data plan.

I also have iCloud storage with optimize storage activated for Apple Music.

The problem I’m experiencing is that when I play a supposedly downloaded playlist, only the first few seconds of a song are actually downloaded and beyond that it starts streaming at LOSSLESS quality, consuming all of my data in a matter of minutes.

This is a very costly issue, and most frustrating as I’ve clearly set the cellular option in Apple Music to high efficiency, which should absolutely not allow lossless streaming over cellular for any reason.

Why is Apple Music behaving this way, and what responsibility does Apple take for the extra costs incurred by the customer for such a glitch?