Originally Posted by
onlySIA
If it's anything like the KrisShop vouchers then they will eventually require you to send it by mail, but in the shorter term you can probably secure the upgrade by emailing a scanned copy to their reservations email address. And I guess you might want to check availability in J before you book that Y seat!
This was the correct answer! Emailed the reservation address and have the business class seat reserved. Thanks!