AFAIK, traditionally, there have not been separate download pages for each pre-release of a new feature (e.g. 3.4.0) or maintenance (e.g. 3.3.5) release.  The usual practice has been to create *one* release page at the usual URI (e.g. https://www.python.org/download/releases/3.3.5) for the first pre-release (alpha, beta, or rc) and then update the contents of that page for each subsequent pre-release through the final release.  The download links for the bits of earlier pre-releases are replaced on the page by those of later pre-releases or the final release.  Thus, even though the pre-release bits are still available to download at their original URIs, the links to them are no longer provided on a download page.  With the transition to the new python.org website near the end of the 3.4.0 release cycle, there were some experiments and changes in process.  In particular, separate download pages *were* created for 3.4.0rc{1,2,3} but not for earlier pre-releases of 3.4.0.  There is no guarantee at the moment that that will happen again for future releases.  If it is important that there be download links for pre-release bits, the release process needs to change and someone would need to go back and re-create those for previous releases somewhere.