Australia to Shanghai, transit to Seoul, back to Shanghai

Can I use the 144 hour exemption with the following itinerary please?
I am flying from Melbourne - Shanghai (transiting in HK), transiting in Shanghai (from Cathay Pacific) to Seoul (Asiana Airlines). I will then return to Shanghai 5 days later and intend to use my valid entry visa on that entry.
I already had flights to Shanghai booked and needed to go to Seoul urgently so have brought the same flight forward.
Thanks!