The more I think about the "business case" Tidal must have evaluated to decide to stream MQA in the (near) future, the more I suspect that they will do the MQA conversion in their app, maybe give you the option to stream MQA "natively", but to have spent gobs to get their library converted and only be able to offer the MQA option to those with an MQA-capable DAC probably doesn't make sense. Plus, from what I've read, MQA is delivered to the DAC in a "PCM wrapper", so I suspect that streaming MQA, converting it in the Tidal app to FLAC and outputting that converted format to the DAC would probably give the benefits of MQA.
Fingers crossed.