I)Are automatically blocked from using Salesforce Classic. II)Can work in Salesforce Classic and Lightning Experience simultaneously using split-screen mode. III)Get a Switcher link that lets them move between Lightning Experience and Salesforce Classic as needed. IV)Stay in Salesforce Classic until they switch themselves to the new interface, after which they can no longer use Salesforce Classic. [bg_collapse view="button-orange" color="#4a4949" expand_text="Show Answers" collapse_text="Close Answer" ] III)Get a Switcher link that lets them move between Lightning Experience and Salesforce Classic as needed. [/bg_collapse]