You might need to access an earlier version of a file, because a file was changed, corrupted, or erased. You might notice the issue only after one or more Snapshot copies were created with the incorrect copy of the file. When looking for the version of the file you need, you should look for it by means of the creation time of the Snapshot copy.
The version of a file refers to the last time the file was modified before a Snapshot copy was created. The access time of a file refers to the Snapshot copy creation time for a file, regardless of whether any modifications were made to that file.
The best way to find all versions of a particular file preserved in Snapshot copies is to use the ls command from an NFS client, or to use the search functionality in Windows.