Triggered before an existing customer record is updated from a CSV file.
The event handler should accept two parameters - the array of imported fields and the customer identifier.
public function subscribeEvents()
{
Backend::$events->addEvent('shop:onBeforeCsvCustomerUpdated', $this, 'csv_before_customer_updated');
}
public function csv_before_customer_updated($fields, $id)
{
// Do something
}