What will a regulated marketplace look like in the United States?

Currently, the e-cigarette marketplace is only partially regulated.  But, FDA has received millions of applications from manufacturers who want to continue to market their e-cigarettes.  The U.S. Courts have required e-cigarette manufacturers to have a marketing authorization from FDA to continue marketing their products after September 9, 2021.  So, what is FDA doing to create a regulated e-cigarette marketplace by September?  How will FDA address youth initiation of e-cigarettes?  For example, how will FDA determine which flavors and e-cigarette types (e.g., open e-cigarettes) will receive marketing authorization?  In addition, to minimizing youth initiation of e-cigarettes, how is FDA going to help adult combusted cigarette smokers have access to e-cigarettes that allow them to switch away from smoking to vaping?