This is especially big step for Wammu as the existing Windows binary was almost five years old. The another problem with that was that it was cross-compiled on Linux and it always did not behave correctly. The current binaries are automatically produced on AppVeyor during our continuous integration.
Another important change for Windows users is addition of wheel packages to python-gammu, so all you need to use it on Windows is to pip install python-gammu.
Of course the updated packages are also on their way to Debian and to Ubuntu PPA.