Originally Posted by lucky9876coins

There are two types of upgrade waitlists, the PA & PB list. The PA list is the Priority A list, which is the first one cleared, followed by the PB, or Priority B list, which is the second one clear. When a 1K uses his/her upgrade instruments they are typically put on the PA waitlist, including when they give their SWU's/CR1's to others, meaning even a General Member with a 1K's SWU goes on the PA list.

Confirmable upgrade instruments, such as CR1's, SWU's, and miles can clear at any time. This means that if I apply for an upgrade today from coach to first on a two class flight (upgraded F is NF), and NF is available, I can clear immediately into First Class and be confirmed. The same is true for an upgrade to Business (NC).