PyPI now rejects new file uploads against any release older than 14 days, closing off a small but useful window that a compromised publishing token could use to graft malicious content onto a trusted, established package. Per the DevOps.com writeup, PyPI has said it is not aware of the technique being used in a real attack yet. The change is preventative.
What the 14-day rule actually blocks
The version stays. The metadata stays. The wheels and sdist you shipped on release day stay. What stops working is adding another file to that version two weeks after the fact.
Normal publishing is unaffected. Cutting a version and pushing wheels and sdist across the same day, or over two or three days while a build matrix finishes, still works. Adding a Python 3.14 build to a wheel set from three months ago does not.
PyPI checked the impact against its own data before flipping the default. According to the piece, only a tiny fraction of the platform's most popular packages had added a Python 3.14-compatible build more than two weeks after the original release went out. The population of legitimate late uploads is small enough that the restriction is worth it.
