Is this the reason why Facebook allows you to change your Facebook E-Mail address once?

[Forrest]

Is the reason why Facebook allows you to change your Facebook E-Mail address once is because if Facebook never let you change your Facebook E-Mail address then someone will know that anyone's E-Mail address will always be in the first name.last name@facebook.com format and because of that someone could contact a stranger or someone that they don't know just by entering their first and last name when trying to contact them at their Facebook E-Mail address?

[justme]

Sorry, your 'logic' escapes me at the moment. Changing your email address will in no way stop someone contacting you if they so wish.