If a person gets blackout drunk how long will they be “blackout”

My bro said he’s blackout drunk tonight and he could hardly stand. It’s not the first time he’s done this and I’ve seen him do it quite often sadly.

To me it seems like if a person drinks that much that quickly they are just kinda screwed for the entire night. He stopped drinking many hours ago but he is still drunk as shit. Will he remember anything from right now tomorrow? He has ate and everything he’s doing fine I’m not worried about his health he’s fine I’m just honestly fricken annoyed by him from dealing with him for the last 8 hours of my life and he is still completely wasted even though he quit drinking many hours ago. I would think it would start wearing off by now but it hasn’t. It has wore down a little since like 8 hours ago but he’s still plastered I can tell you that. I’m just fucking annoyed.