The purchase was reported in a scoop by Axios' Dan Primack, who, according to TechCrunch, obtained an internal memo authored by Luma chairman and co-founder Paul Judge.
You can read the details in both posts.
The web is indeed a cruel mistress. Luma's website--https://lumahome.com--has already all but disappeared from search engines. The site is still up, but appears to be broken.
There is no statement on Luma, First Alert or First Alert parent company Newell Brands websites about either the purchase or what happens to current owners of Luma systems. We've contacted Luma support to ask and will let you know if we hear back.