Funny I had something similar happen. Though they didn't change my email. Once FB started asking for me to send gov ID I just said forget this.
About two months later I got an email saying my account access had been restored. With me doing NOTHING. It seems FB is simply using some sort of automated too long for hackers to care about or be profitable system to monitor account fraud.
I'm beyond caring at this point, but if for whatever reason I get Messenger stripped I'm in for a fun time to try and communicate with some of my west coast friends' group chats.
About two months later I got an email saying my account access had been restored. With me doing NOTHING. It seems FB is simply using some sort of automated too long for hackers to care about or be profitable system to monitor account fraud.