Barred from promotion, what happens now?

Why aren't you asking your superiors? Your 1st Sgt. etc. Why did you fail four promotion boards? It seems the most pertinent questions are those you should answer to yourself...……..

Revolt! Just kidding. Eh, it happens. On the Marine side you generally just ride out your contract unless you are retirement eligible. They could potentially admin separate you, but if you are still working, why would they. If it is because of poor performance or NJPs, if they were going to boot you they probably would have done it already.
It's kind of a wait and see because it is a case-by-case situation generally. Good Luck!

You’ll be barred, COC can review it after 90 days, after the 90 days they will lift your bar, they can’t bar you again unless you mess it up for yourself. Once that happens your Plt Sgt doesn’t have to send you to the board anymore but you’ll start to get counseled on why you are not going back to the board. You haven’t hit RCP and are not anywhere near it. They can not separate you from the Army because you haven’t passed a board in the 4th year of your enlistment. Once you are not barred anymore I would try my best to get from underneath your COC and start somewhere fresh. I don’t see why a COC is allowing a soldier to continue to fail a board 4 times. I hope your doing practice boards in front of other NCOs so you can build confidence. There’s no way you slip past them and then get in front of a whole bunch of senior leaders just to fail 4 times. You COC has to take some accountability for that and that’s why I say get from underneath that COC because it’s not just your fault, it’s there’s as well.

I am never seen a chapter called failure to promote. I have seen Soldiers reach their Retention Control Point. It use to be 8 years as a Specialist. I think it recently changed.

So your best bet is to look into AR 600-8-19 Enlisted promotions and reductions for specifics, as anything I post here will be based on my current understanding. My current understanding is the bar is for reenlistment purposes based on the Army putting an up or out policy on their junior enlisted. If you are barred for a period of six months your unit can start chapter proceedings based on continued misconduct. My experience is if your unit maintains the bar you will just be allowed to ride out your contract and not be allowed to reenlist. As always if your future is uncertain in the military start to prepare yourself for transition. Continue to look for opportunities to advance if staying in is your goal but be aware that that decision could be made for you now and be ready for whatever happens