It would be nice if the check for updates could report what updates are available and prompt user before download begins. Currently, if an update exists it is downloaded first and after that user is prompted to install or not.
This would be especially useful when manually checking for updates.
Have you checked the preferences in the My OSMC updater ? There is already an option that will notify without automatically downloading updates…
If you’re trying to save bandwidth (Hotspot Tethering ?) keep in mind that just checking for updates will download some data, but not as much as downloading the updates of course.