The technology disclosed includes access to content and encryption key rotation in a multi-generational file system that has a first tier file, and automatically initializes a second tier file accessible using a same path and file name as the first tier file. The disclosed technology includes copying forward blocks of data from the first tier file to the second tier file, and prior to completion of the copying forward, responding to an access request by accessing the second tier file by providing data available from the second tier file that has been copied forward and by following links associated with the holes to access blocks in the first tier file to provide data from the first tier file. The first tier files are encrypted using a first encryption key; and applying a second encryption key to encrypt data in the second tier files during the copying forward and write access.