Icarus
What rock have you been hiding under ? Dragonair has been around for over 30 years. You are about 8 years late ... That is when the decent contract ended. But go ahead and apply.
To answer your question. You could get employed on either fleet as an FO. If you were to start as an FO on the A330 you would have to go to the A320 for Command.
If you have the required experience you could get promoted in 12 - 15 months. It would be best to get assigned the A320 if you have over 5000 hours and have previous Jet Command.