code: func (e *Engine) nextCheck() time.Duration {
  	if !e.lastCheckValid() {
  		return minCheckDuration
  	}
  	return e.hoursToNextRelease()
  }
docs: // nextCheck returns the time duration to wait before triggering an update check.
  // It is calculated based on wether there already were a check or enough time
  // has passed. By default the check is performed at the `releaseHourCheck`-th hour
  // of the `releaseDay` weekday.