I think this has already been address offline, but here are the steps.
Menu => About => Account Information -- brings up the Account form.
- Then tap the "Edit" button, and then on the next form tap the "Change" button (top right).
- Then enter your password and tap "Login".
- Then you use "<=" (Backspace) to delete your Email Address until the field is empty.
- Once it's empty the bottom left button text will change to read "Detach From Account" -- tap that, and your device will be removed from your account.
Now you can attach your other Android / iPad instead in the even you upgrade your tablet to a newer model.