Anyone has any experience in releasing the metal pipe from the octapus? any special jag tool maybe?
Seems impossible

 

The black plastic collar towards the front needs to be slid back (away from the metal tube). However, you could carefully cut away the plastic. After you install the new octopus hose onto the metal tube, pull the plastic collar towards the metal tube and it’s locked in place. For future reference, that “special” pos is called a Norma connector.