I believe the OMNI requirement is 180 posts, yes, but also a dual requirement of 180 days on FlyerTalk.
I would also note that rule 14 prohibits post padding in order to reach 180 posts, or any other similar threshold:
https://www.flyertalk.com/help/rules#padding
"Post-padding or other methods of repeated posting to artificially inflate a post count, enhance visibility on the board, or for any other reason, are not allowed."