When your Sky Q box is installed, it's set to Eco. This is the recommended setting as the box consumes less energy by going into low power mode between 2.30am and 5:45am. It won’t go into this mode until any scheduled recordings are complete.
Bringing your box out of Eco mode will take a few minutes and if you try to use your Sky Q Mini box before 5:45am, you may experience connectivity issues. To stop this, you’ll need to switch your standby setting to Active or None.