Roblox retains copies of all uploaded places. This means that any time you make any changes to a place and publish them to Roblox, a copy without these changes is saved as a past version. You can find and revert to one of these older versions at any time. Roblox automatically retains saved versions of each place for version control and backup purposes.
Check out the Reverting to the Previous Versions of a Place Creator Documentation article for more information.
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