The previous certificate was under the rules formulated in 2004, and now the newly revised rules are called 1 1 rules. Including the update of new knowledge, so the crew needs to learn. After learning, they can change the 04 certificate to 1 1 certificate. This training exam is called make-up exam.

Those who haven't changed their certificates have to make up the difference, except the newly graduated crew, because they learned the rules of 1 1 from the beginning.