The script saves the game’s PlaceID and JobID into a text doc called Previous_JobID.txt inside your workspace folder.
Its also recommended to put in your auto exec folder
Here's a example of what would appear in Previous_JobID.text:
Previous: game:GetService('TeleportService'):TeleportToPlaceInstance(123456, 'oldJobId')
Latest: game:GetService('TeleportService'):TeleportToPlaceInstance(789012, 'newJobId')