Hi Alan,
The "patch" or "dev ops" versions in the feature release series (so for the current series, 10.x.y, where x > 0 and y > 0) are usually built to test one or two specific upcoming features. As long as the upcoming features don't involve changes to the Python bindings, the most recent 10.x.0 feature release of the bindings should remain forward-compatible with the 10.x.y release, and so (redundant) wheels are not built and uploaded to PyPI.
Sharp eyes will also notice that wheels are not available (on PyPI) for 10.4.0. This was due to a change in the build process that could not be resolved before the 10.5.0 release. However, due again to a lack of new features affecting the bindings, the 10.3.0 bindings were expected to be forward-compatible with the 10.4.0 HTCondor daemons.
Jason