             customer_id : undefined  # will be looked up if not known
             cb          : undefined
         customer = undefined
+        email_address = undefined
+
         dbg = @_dbg("stripe_update_customer(account_id='#{opts.account_id}')")
         async.series([
             (cb) =>

                        customer = x; cb(err)
                else
                    cb()
            (cb) =>
                if opts.customer_id?
                    @_query

        )

    # Change the email address, unless the email_address we're changing to is already taken.
    # If there is a stripe customer ID, we also call the update process to maybe sync the changed email address
    change_email_address: (opts={}) =>
        opts = defaults opts,
            account_id    : required
            email_address : required
            cb            : required
        if not @_validate_opts(opts) then return
        async.series([
            (cb) =>
                @account_exists
                    email_address : opts.email_address
                    cb            : (err, exists) =>
                        if err
                            cb(err)
                            return
                        if exists
                            cb("email_already_taken")
                            return
                        @_query
                            query : 'UPDATE accounts'
                            set   : {email_address: opts.email_address}
                            where : @_account_where(opts)
                            cb    : cb
            (cb) =>
                @_query
                    query : "SELECT stripe_customer_id FROM accounts"
                    where : "account_id = $::UUID" : opts.account_id
                    cb    : one_result (err, customer_id) ->
                        if err
                            cb(err)
                            return
                        if customer_id
                            @stripe_update_customer
                                account_id  : opts.account_id
                                stripe      : undefined
                                customer_id : customer_id
                                cb          : cb
                        else
                            cb()
        ], (err) =>
            if err
                opts.cb(err)
        )
        @account_exists
            email_address : opts.email_address
            cb            : (err, exists) =>
