Got hold of the UOB Visa Signature card only recently and took it for test drive immediately. The requirement to earn 5% rebate is to spend a minimum of S$1000 of foreign currency equivalent within a statement period. It is stated in the terms and conditions that the regular 1X UNI$ (0.5% rebate) is reflected in the current statement period, and the remaining 9X (4.5% rebate) will only be given in the next statement period.
To be able to make a redemption, however, you need to accumulate at least S$2000 worth of foreign currency spending to earn the UNI$4000 required for redemption. This means you either spend S$2000 one-shot in a single statement period, or S$1000 each in two statement periods.
True enough, i received the 9X UNI$ in the statement for the following month. So, i declare the test drive successful and i’m ready to use this card during my upcoming trip.
Managed to do my first S$100 redemption after my trip. Next month, I’ll be able to redeem another S$100.
Update 19 Apr 2018
Unfortunately, UOB has quietly axed the special 5% rebate promotion. To redeem S$100 worth of cashback, one has to earn 8700 UNI$, which means the cashback rate is only 2.29% now. Nevertheless, if you pump petrol at SPC, you can do an instant rebate redemption of 600 UNI$ in exchange of S$10 worth of offset, and this works out to 3.33% cashback, which is somewhat worthwhile.