Grouped by month. Fixes are constant and mostly uninteresting, so this lists the things that change what you can do.
The web app updates itself. The desktop app prompts you when a new version is available, and you can always reinstall from the download page.
Yes. Administrators see a What’s New panel after a release, and anything that changes a workflow is explained there.
Yes, and a good number of the items above started as somebody’s message. Email us or raise it inside the app.
Not published. We would rather tell you honestly whether a specific thing is coming than maintain a list that slips.
Continuously for the web app, and every few weeks for the desktop app.