Issue with Signing Up Using Previously Deleted Email

After deleting a user, when I try to sign up with the same email, I get the following error: {"message": "A user with the same email already exists in the current project.", "code": 409}.

TL;DR

Developers experiencing issue with signing up using previously deleted email; encountering error message {"message": "A user with the same email already exists in the current project.", "code": 409}. Solution: Wait for cloud account deletion to be fully processed before reusing email for signup.