Try rs/push and rs/chanpush.
There are two different cases here. Changing the email address from the webif settings actually creates a new user account and moves the existing device over (so to expand on what BH has said above, the device settings, including auto rules, will be untouched but the old account settings will be lost). I should allow changing the email address within RS settings though- it's now on my job list!af123: wouldn't it be more logical/intuitive to have the email address as an RS setting rather than a WebIF setting?