Do I need a visa for China for a cruise or apply for 144hour visa?

Hello , We are party of 2 flying from Sydney, Australia to Shanghai, staying 3 nights 21 August 2018 to 24 august 2018. Check out of hotel the 24th August. Then go to Wusongkou International cruise terminal for cruise. The first port after Shanghai will be Busan (South Korea), then Hong Kong, Nha Trang, Ho Chi Minh City, Singapore. After Singapore we will go to Sydney.

Cruise line Princess tell us that many guests embarking in Shanghai may not require a Chinese visa for this voyage if: 1) You arrive in Shanghai directly from a country other than China or the first country other than China visited on the cruise; 2) You embark your cruise within 144 hours of arrival in Shanghai.

Is it true?
Can we apply for 144 hour free trasnit in Shanghai in that case or do we apply for Chinese entry permit in Sydney before we leave?

Best regards

Oleg