Guest sessions
The calculator signs you in anonymously so plans can sync. Guest accounts and their plans are deleted after 30 days without activity. Clearing browser or app storage on a device also drops that guest session. Export a JSON file first if you want a backup.
After you save an account
Plans tied to an email and password stay until you delete them. You can delete a plan inside the calculator. If you remove someone you shared it with, they lose access but your plan stays put.