Access to account after changing email of root user.

When you change the email address associated with your AWS root account, it's normal to experience a temporary delay before you can access your account again. This delay is due to the propagation of the changes across AWS systems. Typically, changes to an AWS account can take up to four hours to fully propagate everywhere.

If you're still unable to log in after several hours, there are a few steps you can take:

1. Double-check that you're using the new email address to log in. The old email address will no longer work for authentication.

2. Ensure you're using the correct password. If you're unsure, you may need to go through the password reset process using your new email address.

3. Check your new email inbox for any confirmation messages or additional steps required to complete the email change process. AWS typically sends a confirmation email to the new address.

4. If you continue to have issues after 24-48 hours, it's recommended to contact AWS Support. You can open a case under "Account and billing" which can be done free of charge. They can assist you with regaining access to your root account.

Remember, changing the root user email is a significant account modification, and AWS implements these delays as a security measure. In most cases, you should regain access within a few hours, but patience may be required as the changes propagate through the system.
Sources
Once a root account is changed, how long does it take to gain again access to it? | AWS re:Post
ROOT account change e-mail? | AWS re:Post