When do you put the number 2 on your Non-Commissioned Officer ribbon, after completion of the course or after you get pinned?

In the Q-course there are PFCs that wear a #2 on their NCOES ribbon. Totally legit.

After you complete ALC and you update your ERB.

After the course completion

Officially i had to wait till it was on my erb

When you have the 1059 in your hand.

If you have completed the course you wear the award. If you didn't wear it you would be out of uniform. That device has nothing to do with your rank. It acknowledges that you have completed the course and that's all.

After completion of coarse,

Did you get your NCOPD ribbon upon graduation of WLC or promotion to SGT?

once you have your 1059

Should pin it on after receiving official orders