Would like to confirm if I qualify for a 144hr visa

I am leaving Sydney Australia on 30/4/20 stopping in Singapore for 3 hrs then travelling on to shanghai landing on 30/4/20 I am leaving on 2/5/20 to go on a 16 day cruise on the sapphire princess our first port of call is Busan in South Korea our last port of call is Singapore on the 28/5/20 thank you for any information