Back in March 2019, I threw up this Blog on Salesforce Auto-Transition to Lightning Experience.
So a few things have changed that warranted an update so I figured to keep it simple, I'd bring you another blog post.
So first things, first. Ignore that other blog post. It's a brave new world and I hope to break it down for you.
Starting with Salesforce Winter '20, there is a Critical Update called "Turn on Lightning Experience" that will be auto enabled on October 11, 2019 (your date may vary depending on when your instance is upgraded to Salesforce Winter '20).
You'll probably notice this Critical Update is already active in Org. However, on or about October 11th, the Critical Update will go into effect. So what exactly does this critical update do?
First, it will automatically turn on Lightning Experience in your org. What we mean by this, is that after the Critical Update is made permanent, when you navigate to Lightning Experience Transition Assistant and click on "Get Started"
and then navigate to Path 2 Roll Out Phase and click on "Go to Steps"
and finally go to Step 4, Launch Lightning Experience, the "button" to turn on Lightning Experience will be set to On, however, it will be grayed out as you will not be able to turn off Lightning Experience from this point forward.
Any out of the box Salesforce profiles, such as System Administrator, Standard User, Standard Platform User, will all have the "Lightning Experience User" permission turned on by default.
How can you determine what a Salesforce out of the box profile is? When you navigate to Manage Users | Profiles, you'll see a list of all the profiles in your Org. Any profiles whose only actions are Edit and Clone are Salesforce out of the box profiles. All other profiles that have Edit | Del | Clone are really custom profiles; that includes profiles you may commonly associated with BMC Helix Remedyforce such as ServiceDesk Staff or ServiceDesk Client.
If you have users assigned to any of the Salesforce out of the box profiles, those users will find themselves now in the Salesforce Lightning Experience. Other users that may be in customer profiles may not find themselves in the Lightning Experience, but if they do, that means more than likely either their profiles has the Lightning Experience User permission enabled:
Or they may have a permission set assigned to them where the Lightning Experience User permission has been granted to them.
Keep this in mind if you have users who may not be ready for Lightning. You'll probably want to do a review in anticipation of this change and take the appropriate actions. Additionally, after October 11th, keep in mind if you clone a Salesforce out of the box profile, that the Lightning Experience User permission will be enabled by default.
For additional details or questions, we refer you to the Turn On Lightning Experience Critical update FAQ. Please note that Salesforce Classic is still available; however, users may find that have to switch back if that is their preference and they fall into an standard profile.