Before which point must it be done ? I wouldn't like to lose my account 
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...According to this you won't need a valid email to move your account to the finished version, only to test the beta.
Although I'd check that with a staff member before relying on it in case things have changed.
err.... any way to get my password reset without an email?
No. You could create a separate account using a throwaway email service.
With the final version, there will be a way to move your account without having a valid email.