I checked the source code for creation of a new user, but did not find anything related to Synthea. However, as per the code, whenever a user logs in, and sees a list of sandboxes, the list is comprised of the following:
All sandboxes associated with the user (table user_sandbox)
All sandboxes that have public visibility
Shilpy will send out an email informing users that the Synthea sandbox is being removed. Two weeks after that, the sandbox will be removed (from view).
Need to remove access to the Synthea Sandbox on 10/23.
In addition to changing the visibility of the Synthea sandbox to Private, I needed to remove associations of all users with that sandbox from table user_sandbox. I have not removed the sandbox schema from the database. I have attached a dump of the table before the associations of the sandbox with users were removed.
Since I needed to remove all user associations with the Synthea sandbox from table user_sandbox, I thought I should make sure that these associations do not get created when a new user registers with the sandbox. I registered as a new user and when I logged in, I saw an empty list in My Sandboxes. Also verified that the table user_sandboxdid not have any Synthea sandbox association for the new user.