The last release was in Jul 2022. I am sure several fixes and enhancements since then. What is the plan for the next release?
At some point, we will add a roadmap page to the website, but for now, this has probably only been discussed on the developers mailing list. At the moment there are no definitive plans for the next release. If you want to get the latest enhancements and bug fixes, you need to use one of the formats which is built for each commit, such as Appimage. You can get the latest from the 5.1 branch (mainly bug fixes, not many enhancements) or from master branch (all bug fixes and enhancements.
At some point, hopefully within a few months, the team will release a version called 5.2. This will be from master branch, which will then become the stable branch. Depending on how long this actually takes to happen, there might be a 5.1.4 release. 5.2 will have lots of enhancements, and it includes many changes preparing for the conversion from Qt5 to Qt6, but that actual change will follow 5.2, again, by probably several months. As I said, not of this has any definite schedule.