There have been several new and updated packages in Humble since its last sync a couple of weeks ago and it’s time to sync those new features and fixes to the main apt and dnf repositories.
There are currently no regressions and 204 packages to release.
We will start holding rosdistro PRs for the sync today (2025-09-19) and will plan to do the sync on 2025-09-22.
Actually, sync is out already
I checked on rosdistro and there were no merges on Humble for the last few days so I just went ahead with it.
Maybe the information is in some documentation but I wonder : what is the trigger for a new sync ? 
In my experience, it’s mostly vibes.
Usually when a particular distro has collected enough new package releases, the “ROS boss” for that distro (see Distributions — ROS 2 Documentation: Rolling documentation ) decides to kick off the sync process and announces it on here.
Roughly, this ends up being once a month or so.
I try to do a sync every 2-3 weeks and a patch every 2 months or so.
My wife and I had a kid a few months ago, so I haven’t been very good about this.
At the moment, I’d like to do syncs a bit more frequently so things get in before ROSCon.