When requesting an account e-mail change, the existing e-mail will remain in place for anything e-mail related the service does for your account until the new e-mail address is verified.
If you are locked out of your existing e-mail address and forgot your password, while that is extremely unfortunate... that is no excuse to compromise operational security on the network. If you are locked out of your existing e-mail address we will work with you on confirming your identity to provide access to your account.
However, the burden of proof is on you.
It is advisable to update your account details with proper contact information.