code: private function checkIfAccountIsActive(User $user): void
      {
          /** @var Config $config */
          $config = $this->framework->getAdapter(Config::class);
  
          $start = (int) $user->start;
          $stop = (int) $user->stop;
          $time = Date::floorToMinute(time());
          $notActiveYet = $start && $start > $time;
          $notActiveAnymore = $stop && $stop <= ($time + 60);
          $logMessage = '';
  
          if ($notActiveYet) {
              $logMessage = sprintf(
                  'The account is not active yet (activation date: %s)',
                  Date::parse($config->get('dateFormat'), $start)
              );
          }
  
          if ($notActiveAnymore) {
              $logMessage = sprintf(
                  'The account is not active anymore (deactivation date: %s)',
                  Date::parse($config->get('dateFormat'), $stop)
              );
          }
  
          if ('' === $logMessage) {
              return;
          }
  
          $ex = new DisabledException($logMessage);
          $ex->setUser($user);
  
          throw $ex;
      }
docs: Checks whether the account is not active yet or not anymore.