144 hours transit visa for cruise passengers

Hello,

We are party of 2 flying from Sydney, Australia to Shanghai, staying 3 nights from 21 August 2018 to 24 August 2018. Check out of hotel the 24th August.
Then go to Wusongkou International cruise terminal for cruise back to Sydney. The first port after leaving Shanghai will be Pusan (South Korea), following to ports at Vietnam, Hong Kong, Singapore before coming back to Sydney. Can we apply for 144 hour free transit in Shanghai or shall we apply for Chinese entry permit in Sydney before we leave?

Best regards

Oleg