As a best practice, maintain consistent use of version numbers for each software update.
It is tempting to simply upload a fix to a current production directory. But if there are problems, this approach doesn't permit quick roll backs. This approach can also cause unnecessary delays in addressing a potentially critical situation.
Using version numbers consistently helps development and support teams diagnose and fix issues in a timely manner. If a new version causes issues that were unknown during the test phase, support can roll back to a previous known working version. Being able to roll back is especially helpful if a version makes the system unstable and support is required to respond in a 24x7 environment. With versioning, the development team can review specific code fixes within the context of multiple previous versions.