Or if you booked via the EK website, why not do a dummy upgrade on your current booking and see what price you get and see if it's comparable with the offer your parents got and if happy go ahead and book it. If booked via a TA, contact them and ask how much it would be to upgrade your ticket. There is also the added advantage of increasing your miles towards getting Silver.

I am by no means an EK expert and my upgrades were done through my Corp. TA and considering two long haul flights GLA-DXB-PEK on the outbound, I got a price of £640 to upgrade to J which I thought was very reasonable. This also gave the added value of Chauffeur service (for the GLA departure only on your itinerary), GLA Lounge access which I thought was an excellent lounge for comfort and food/drink offerings (although I didn't notice any Irn Bru), Lounge access in DXB and extra baggage allowance.

I may be mistaken but I don't think the upgrade offers via e-mail give you all of those advantages but am prepared to be educated properly by the experts .

Safe & Happy Travels

S