Is there a way to know the flight number?

[chaitanya]

I flew on Cathay Pacific from Delhi to Bangkok on 12 June 2012. The flight was actually DEL - HKG via BKK but I had to get off in BKK.

Also BKK to SIN, SIN to BKK and BKK to DEL in the next few days, all on Cathay Pacific.

But these legs are no longer operated by Cathay Pacific Is there a way to know the flight number?