“...allowed her to continue for 30 days.”
They did no such thing.
https://www.foxnews.com/politics/michigan-supreme-court-whitmer-coronavirus-ruling
So, per this Fox summary, I was accurate in that the MI governors emergency edicts after the initial declaration were ruled by the State supremes to be in violation of state law. The state law in question allows the Executive an initial unilateral 28 day declaration of an emergency after which the MI governor is required to receive approval from the Legislature in order to extend. The governor did not request nor receive this approval. Thus, the ruling invalidated all Executive emergency edicts since late April 2020.
Since then though, the MI governor stated that the existing edicts would continue in effect for 21 days, which was through late October 2020, and would continue longer via other authorities she has. Im not sure if she has followed through with these other authorities.