Who knows!

This is also interesting (from the MQA website Q & A section)
Originally Posted by MQA website
How do I use MQA on packaged media such as CD, DVD or Blu-Ray Disc?

Every mastering studio that is certified as an MQA provider will have a tool to convert 24-bit MQA files to MQA16 files for use on CD. 24-bit files can be authored directly to DVD or Blu-Ray Disc without a change of format."
This seems to imply that MQA may well be issued on CDs

Also:
Originally Posted by MQA website
How does MQA work for existing recordings already on a service?

MQA can run as a process on existing digital files already in your catalogue. The encoder can analyse and remove all the unwanted artefacts in the music – but it will be most effective when employed with the original master tape so that it can take into account all of the processes introduced in the chain.
and
Originally Posted by MQA website
How many tracks per day will run through the MQA encoder?

Conservative estimates indicate that the encoder can process approximately 100,000 tracks per day with access to an HSM module on its internal network.
A clear indication that existing recordings may simply be bosched through the MQA encoder to give an MQA file. Nothing wrong with that, but it is straying from the original end to end concept of MQA, and a clear indication that there will be different levels of MQA-ness. I doubt whether we will know exactly what we are getting from every seller. The "little blue light" will not help in this regard.


Streaming: Roon, NUC, QNAP869 NAS
2ch system: dCS Vivaldi, Audionet Stern, Audionet Heisenberg, Magico Q1
Retro system: 101/104/105, Red Rose Spirit