Hi Niftynita
I have been advised by our aviation team that this tour is currently being operated with Vietnam Airlines who do not currently offer an online check in.
In terms of a flight upgrade, unfortunately we don't have a flat price list, these are based on availability with the airlines and can fluctuate. I would recommend that your contact your travel agent who will be able to discuss this with one of our holiday advisors.
Kindest regards,
Julia