Updates "Last checked" is before last update installation time
With Automatic Updates enabled, Software found some Flatpak runtime updates to install (though they were not installed automatically, see #540 (closed)). However, after installing those updates, the "Last checked" time on the Updates page says that the last time updates were checked was several hours before the updates were actually found (the time shown is from the previous boot).
Perhaps the "Last checked" time is when package-based updates were last checked, not Flatpak-based ones? Or maybe automatic update checks don't update the last checked time?