Thank you so much everyone! I will see what happens since the hut has been removed.
I'm so glad you removed the "Snuggle Hut", they are totally unsafe, that's the main-reason that you should remove it, the hormonal issues they encourage are just another side-reason to never use them...There have literally been
thousands of pet birds/parrots that have been killed by having a "Snuggle Hut" and/or a "Happy Hut" inside of their cages (same things, two different manufacturers/brands); it seems to be a 50/50 split between them dying from a blockage in either their GI Tracts or their Crops from them eating little bits of the material, and then from them literally "hanging" themselves by freeing a thread from them while chewing on them,
and then getting either their necks wrapped up in them and dying from actual hanging, or they get their legs caught in the loose threads and hang upside down all-day, until their owners come home and they have either bled to death from chewing their own legs off (or trying to), or from the thread actually cutting through their legs. Here is a link to one of the hundreds and hundreds of websites/forums where people are listing the deaths of their birds due to a "Snuggle Hut" or "Happy Hut"...
Happy Hut Warning
Anyway, just keep in-mind that at 9 months-old he is also going through puberty anyway, so removing the Snuggle-Hut should calm him down significantly, and if he was having any really aggressive, violent "episodes" after being inside of his cage, then they should stop, because those were no-doubt related to the Snuggle-Hut...I cannot explain to you how horrified I was when my Bowie went under the couch that one time...I couldn't find him, I looked all over the house and I was calling to him but got no answer, so I was sure he was dead or dying somewhere or that he somehow got out of the house and was gone...But finally I found him, under my couch (which is extremely low), making a little "nest" for himself out of crumbs, change, Cheetos, lol, anything he was finding under the couch...I called to him and he wouldn't come out for anything, and the entire time he was under there he was "talking to himself" in this extremely soft, rambling kind of voice, with this constant, soft "chirping"...It was creepy, he just stared at me but it was like he was in a trance or something...So finally I got a yardstick and gently swept him towards the front of the couch, and when he finally came out from underneath, he literally "charged" at me, ran purposely towards my hand and latched-onto it and wouldn't let go! Blood dripping, it was like having a vampire bat stuck to my hand...Once I managed to pry his beak off of my hand, he fell to floor and ran right back under the couch...I went and cleaned-up my hand, then again used the yardstick to sweep him out from under the couch, this time careful to not let him bite my hands....Well the second time he again "charged" at me, but at my feet!!! He then latched onto the skin on the top of my foot and wouldn't let go!!! It hurt so badly, I was trying to not start screaming at him, but this time he wasn't getting away...I walked to bathroom with Bowie attached to the top of my foot and managed to pry him off of it, this time I got hold of him around his body and did the "Vet-Hold"...And he went back into his cage for an hour, and after that he was completely normal and it's never happened since (I've blocked-off everything since so he can't get underneath ANYTHING)...
So that's just how hormonal being in small, dark places they can become...but just remember that your guy is going to still be hormonal for a couple of months, it will gradually get better, and the first time they go through this is obviously the worst...So removing the Snuggle-Hut should help quite a bit, but don't get discouraged if he's still moody, cranky, nippy, etc. for the next couple of months, as puberty in birds is no different than puberty in a teenage human...they turn into little monsters, lol...
My best advice is that whenever he's out with you and he become nippy, don't act like you're "punishing" him, don't scold or yell at him, because it's not his fault, he isn't doing this because he's angry or wants to hurt you, it's just his hormones going bonkers...I would just quietly put him back in his cage for a few minutes to calm down if he becomes nippy when he's out. Now that the Snuggle-Hut isn't in there anymore, a few minutes in his cage by himself will actually help to settle his hormones and calm him down (I'm sure that putting him in his cage didn't help but probably made it worse when the Snuggle-Hut was there)...