Popular advice here for those booking multiple first class awards on CX is to take whatever is available in first, book the remainder in a lower class, and then hope to upgrade those close to departure.

I want 2 round-trip award bookings in first. Even with a pretty fair amount of flexibility in departure dates and airports, I'm having trouble finding the right combination. So, some questions.

1. Inbound availability in first is good, but I find outbound availability in economy only. Will CX allow me to book economy outbound and first inbound?

2. Assuming upgrades become available, can economy be upgraded to first? Or do you have to upgrade to first from business?

3. If I have to book both in economy, what are the odds of upgrading both close to departure?

Thanks in advance for any help.