Direct Flights from SIN (Singapore Changi) to PVG (Shanghai Pudong) on December 17th, 2009 . BTW There are no flight to Hongqiao Airport. It mainly serves Korea and Japan and domestic flights.
China Eastern Flight MU 544
Departed:1:03am (8 min late)
Arrival Time(Actual is unknown): 6:10am
Singapore Airlines Flight SQ826
Departed: 1:18 AM (3 min late)
Arrived: 6:19am (6 min early)
Singapore Airlines Flight 828
Departed: 7:31 am (4 min early)
Arrived: 12:52 pm (7 min late)
Singapore Airlines Flight 830
Departed: 10:05am (on time)
Arrived: 4:11pm (56 min late)
China Airlines Flight 546
Departed: 11:52am (1 hour 40 min late)
Arrived (Actual Not given): 3:10pm
Next two flight arrive too late. Screenshot below
Apart from these, they could have transfered from many cities like
Shenzhen
HongKong
Macau
Beijing
Taipei
Xiamen
Guangzhou