What changed, and when.
Every release, written in sentences rather than commit messages. Reina shows you this same list on the Updates screen when installing an update. It is literally the same file, so the two cannot disagree.
Nothing to show right now. Either no release has shipped yet, or the notes host is briefly out of reach. Reina's own Updates screen carries the same list either way.
Reina checks for these without being asked. Updates are opt-in and shown before anything is installed: the app tells you the version and the size first, keeps the previous version so you can go back, and can show you these notes the first time it launches on a new one. Nothing installs behind your back.