Originally Posted by swintonowl
Depending on what vouchers you have you may only be able to upgrade from a certain fare type, I think it says this on the voucher.
I would not normally use a voucher to upgrade on a shorthall flight, however it would probably be worthwhile with SAS since the difference between business and economy is pretty big.
I wouldn't upgrade for a shorthaul - but all my longhaul are on a BA and the voucher runs out in Feb. Shame to waste them.