http://track-chinapost.com/startairmail.php shows all these parcels were shipped from China to Switzerland in mid of March. They are still in China.

China government has cancelled 99% international airlines to stop cover-19 spreading. China Post has no shipping space to send parcels abroad. Many parcels of February are still waiting in China airports. You might need wait some more time.

Right now it is difficult to predict accurate arrival time. It should be after the covid19 crisis ends and international airline back to normal.