Is Apple Music playing losslessly of if I use an macbook as an Airplay receiver?

I noticed on my dac the bitrate received from the Wiim Pro dropped from 192khz to 44.1khz when using Airplay, which prompted some googling. I learned Airplay uses 256kb/s stream, which frankly sucks. So much for convenient hi-fi.

My workaround is using a macbook into the same dac via usb. I learned that one has to set the bitrate manually in the midi settings for it to send high res audio, so everything seemingly is upsampled to 192khz. The dac does display this figure when Mac is connected. It sounds by all means good, but is it the full potential?

The trouble now is I have no way to confirm what the stream from Apple Music actually is. And I would like to use Airplay to control the Mac, as it is by far the most user friendly, much more than Remote.

But I really want to know if this method sends the lossless and highres streams to the dac, or is this also downgraded to lossy streams?