UOB has extended an ongoing promotion, allowing you to earn 6 mpd on selected hotel and flight bookings with Expedia, well into 2019. From now until 30 Apr 2019, book your next trip here and earn 6 mpd when you use your UOB PRVI Miles card. The trip must be accomplished by 31 Jul 2019.
Be sure to check the participating airlines in this promotion as they may change from time to time without prior notice.
Full terms and conditions can be found here.
This is actually not the best promotion with Expedia. From now until 31 Jul 2018, use your Citibank credit card with Apple Pay on Expedia and earn up to 8 mpd! You can find more information on this here.