One of the goals of IUS is to remain inline with upstream stable sources. That said, anytime a new source update is available an update is general acceptable. That said, the developer has full right to skip a source update under the following conditions:
- The update is not applicable to the project. I.E. A fix was applied for a specific operating system that IUS doesn’t support.
- The update does not have any security fixes. Any security fixes needs to be applied asap. Alternatively security and major bug fixes can be backported if preferred.
- The update significantly breaks backward compatibility (which should not happen in a minor release update... so if it does be sure to wag your finger at the upstream devs and let them know what the business is).
It is very common that backports to RHEL packages and updates in the current version of Fedora might apply IUS packages. We call this back-up-porting. This is sometimes required to get security fixes applied before the next upstream stable source release. Doing so takes a more intimate knowledge of the source of your package and should not be done without caution and thorough testing.
We also follow changes in Fedora to remain inline with what users expect. For example, adding a new subpackage for PHP or changing a default config setting. Changes like this should applied to IUS packages where possible and compatible with previous versions.
Some upstream devs don’t really have any concept of release management and just push out new updates whenever it is convenient. Though IUS is following upstream stable, we also kind of want to take the precautions to keep our releases as stable as possible. A good rule of thumb is to let a number of changes/fixes/etc acumulate and pushing out one larger update. Updates should be done no more than once every two weeks [preferably once a month] for the same package, unless a security or major bug fix is required.
Our goal as packagers should not be zero day releases [to stable] for new upstream stable sources. Getting a zero day release out to testing is great, and by all means please do. But be sure that update gets proper testing before making it to stable.