Winter '23 is coming with lots of new features. Use your sandbox to get early access to new features and test your configurations before the production upgrade.
Winter ’23 is coming with lots of new features. Use your sandbox to get early access to new features and test your configurations before the production upgrade.
The sandbox preview window for Winter ’23 opens August 26, 2022. If you have already have a sandbox or if you spin up a new Sandbox instance by August 25, 2022 (the day before sandbox preview) then you can take advantage of the preview.
First, decide whether you want to:
After you decide:
In most cases, no action is required because your sandbox is already on a preview instance.
Pre-Release Org for Winter 23 will be available on August 11 2022
Preview release notes will be available on August 17th 2022
The sandbox preview is a 4-week window before Salesforce does the major Salesforce release when all preview sandboxes are upgraded to the next major Salesforce release.
As you already have sandbox so it’s your first chance to test the new configurations of customisation on the new/upcoming release.
If you have a sandbox and that is a NoN-Preview Sandbox and you want that sandbox to be a preview sandbox so that you can test the new customisation then you need to refresh the sandbox to get a new instance.
For more information, Follow the Trailhead Module
Note: – Your Sandbox Refresh must be completed between now and August 25, 2022 to route all sandbox requests to preview instances.
On August 26, 2022, Salesforce will reset all incomplete sandbox requests to a non-preview instance.
Find your sandbox details
In production, from Setup, in the Quick Find box, enter Sandbox, and then select Sandbox. Use the Location column to find your sandbox instance(s).
Is your sandbox on a preview instance?
Use the Sandbox Preview Guide to determine if each of your sandboxes is on a preview or non-preview instance. View the full list of preview and non-preview instances.

Understand the cutoff date
Every release we give you a cutoff date for sandbox refresh completions. Usually it’s the day before the preview starts.
Read the help article provided by Salesforce
https://help.salesforce.com/s/articleView?id=000357271&type=1