Hi louist,
For miles awarded in the manners stated above, the Voyage miles have to be converted into KrisFlyer miles.
Spend in SGD overseas earns 1:1, which is as you've said, lower that local general spend.
^WX
I read the terms and conditions on 13 Jan 2018, it show the followings:
OCBC VOYAGE Credit Card only
1.1.1 Overseas Retail and Dining Spend: earn 2.3 VOYAGE Miles for every S$1 equivalent charged in
foreign currency to the Card. For the avoidance of doubt, any overseas dining spend charged to the
Card in Singapore dollars will earn VOYAGE Miles at a rate of S$1: 1.6 VOYAGE Miles. Any overseas
retail spend charged to the Card in Singapore dollars will earn VOYAGE Miles at a rate of S$1: 1.2
VOYAGE Miles;
OCBC Premier VOYAGE Credit Card, OCBC Premier Private Client VOYAGE Credit Card and Bank of
Singapore VOYAGE Card only
1.1.4 Overseas Retail and Dining Spend: earn 2.3 VOYAGE Miles for every S$1 equivalent charged in
foreign currency to the Card. For the avoidance of doubt, any overseas retail and dining spend
charged to the Card in Singapore dollars will earn VOYAGE Miles at a rate of S$1: 1.6 VOYAGE Miles;