If you ring the eService Centre, can they help you get a Gold/Diamond seat guarantee or can only the reservations department do that?

And can they help you get the seat guarantee 24/7, or only during normal HK working hours?

And if you ring the eService Centre to complete a booking, and you pay via Citibank CX credit card, will you get the bonus miles that you would get if you did an online booking?

Thanks!