Update readme explaning prs and milestones

Author: jjw24

README.md

@@ -288,6 +288,12 @@ Yes please, let us know in the [Q&A](https://github.com/Flow-Launcher/Flow.Launc
 
 ## Development
 
+### New changes
+
+All changes to flow are captured via pull requests. Some new changes will have been merged but still pending release, this means whilst a change may not exist in the current latest release, it may very well have been accepted and merged into the dev branch and available as a pre-release download. It is therefore a good idea that before you start to make changes, search through the open and closed pull requests to make sure the change you intend to make is not already done.
+
+Each of the pull requests will be marked with a milestone indicating the planned release version for the change.  
+
 ### Contributing
 
 Contributions are very welcome, in addition to the main project(C#) there are also [documentation](https://github.com/Flow-Launcher/docs)(md), [website](https://github.com/Flow-Launcher/flow-launcher.github.io)(html/css) and [others](https://github.com/Flow-Launcher) that can be contributed to. If you are unsure of a change you want to make, let us know in the [Discussions](https://github.com/Flow-Launcher/Flow.Launcher/discussions/categories/ideas), otherwise feel free to put in a pull request.