On my previous team I used to think read only Friday was a good idea, but it was in fact a symptom of quality problems. My current team has a strong culture of testing and quality and we ship whenever the feature is ready.
For isntance if your whole company is at a yearly retreat in some vacation park, including part of the SRE team, but two or more devs are still working for whatever reasons, would they ship a full refactoring of some service ?
I'm always interested in where the boundaries are, if you could share.