If you would like to change the Xbox account you are currently using to access the Bleedingedge.com website, you can simply logout and enter different details when you are asked to sign in again.
If for any reason you are not prompted for your Microsoft credentials and you are automatically logged back into the previous account, go to www.microsoft.com and log out of your Microsoft account.
When you revisit the Bleedingedge.com website you should be prompted for new credentials upon your next login attempt.