Mifepristone and Dawn phenomenon

In submitting a topic about the dawn phenomenon, a thought occurred to me that I wanted to raise the profile of, in case nobody saw my original post.

If the dawn phenomenon is due partially to an increase in cortisol, what would happen if you took a glucocorticoid receptor blocker such as mifepristone in the early hours ?

I’m very tempted to try this if I can lay my hands on some mifepristone.

Any thoughts ?