I won't go into all the dreadful details, but in a nutshell it make it possible to do the new release without a large amount of extra work.
All of the original v9.4.1 builds remain available online, but in a "v9.4.1" sub-directory. If the current v9.4.1 SP1 download URL is this:
then the previous non-SP1 v9.4.1 download will be available here:
I would recommend using the SP1 builds. The original v9.4.1 builds are available for emergency use -- just in case some unforeseen problem exists with a new SP1 build.
answered Aug 20 '13 at 17:54