When the retention period for an object ends in Snowflake, Time Travel on the historical data is dropped . This means that the ability to access historical data via Time Travel is no longer available once the retention period has expired2.

In Snowflake, the default access level for any securable object (such as a table, view, or schema) is "No access" until explicit access is granted. This means that when an object is created, only the owner of the object and roles with the necessary privileges can access it. Other users or roles will not have any form of access to the object until it is explicitly granted.
This design adheres to the principle of least privilege, ensuring that access to data is tightly controlled and that users and roles only have the access necessary for their functions. To grant access, the owner of the object or a role with the GRANT option can use the GRANT statement to provide specific privileges to other users or roles.
For example, to grant SELECT access on a table to a specific role, you would use a command similar to:
GRANT SELECT ON TABLE my_table TO ROLE my_role;
Reference: Snowflake Documentation on Access Control (https://docs.snowflake.com/en/user-guide/security- access-control-overview.html)