October 7, 2019 Note: Due to an unforeseen technical issue, the "Turn on Lightning Experience" critical update has been delayed to January 7, 2020. See this post for more details: https://success.salesforce.com/0F93A0000009SE1
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Users will still have access to Salesforce Classic when Lightning Experience is turned on. But Lightning Experience is where you want to be! It’s where all new Salesforce innovation happens, with reimagined classic functionality and features that are exclusive to Lightning Experience. Moving to Lightning Experience benefits everyone, from business leaders and users to admins and IT teams.
What changes will users notice when the Critical Update is activated? Only users who have the Lightning Experience User permission get access to the new interface. This includes all users with standard profiles, any users with custom profiles where the permission is enabled, and users who’ve been assigned the permission via a permission set. These users get the Switch to Lightning Experience link in the Salesforce Classic header. And once a week, Lightning Experience-enabled users who are working in Salesforce Classic will be automatically logged into Lightning Experience. Users can switch back to Salesforce Classic as needed.
Wondering how to prepare for Lightning Experience? Use the Lightning Experience Transition Assistant, your one-stop shop with step-by-step guidance, tools, and resources. And check out the Winter ‘20 Release Notes (https://sfdc.co/buhC1i).
Rather watch a video to get the 411 on this Critical Update? Here you go: https://sfdc.co/gKgEl.
