You can preorder the Xbox series X or Series S on shopcgx.com which is a cost guard online exchange. You have to be in military/veteran.
If you have access to shopmyexchange and navy exchange then you can setup an account and are able to preorder it. It states that it should ship in Nov.9.
If you any one is interested in getting an Xbox series X preorder and missed out, this is your opportunity. This is a reputable website and I have order from there before.