Tylko zauważ, że task się uruchamia co zadany X czasu, a queue jak się skończy to.. tyle.. Trzeba ręcznie "wzbudzać".
Tu masz jeszcze rozpiskę:
/**
* Queue a background task
*
* @param string $app The application that will be responsible for processing
* @param string $key The key of the extension that will be responsible for processing
* @param mixed $data Data necessary for processing
* @param int $priority Run order. Values 1 to 5 are allowed, 1 being highest priority.
* @param array $checkForDuplicationKeys Pass keys to check to prevent duplicate queue tasks being added
* @return void
* @throws \InvalidArgumentException If $app or $key is invalid
*/
public static function queue( $app, $key, $data = NULL, $priority=5, $checkForDuplicationKeys=NULL )
Parametr oczywiście $priority.