Asiana Club - class upgrade with OZ miles on *A

Hi,

I look now if I stay with M&M or if I go to OZ.

Usually, I use my miles to upgrade between Y and C or C and F. ..
Is it easy to use your OZ miles for an upgrade *A or there is very little availability

Thank you

Availability is the same as award ticket inventory I, X. But *A upgrades require full Y or B class booking, which sometimes can be even more expensive than discounted business class.....