Flight Changi Airport departs from Singapore Changi Airport at 12:45 and arrives at Bandar Seri Begawan Brunei International Airport at 15:00.
The flighttime is about 2h 15m. The distance travelled ("as the bird flies"): 1223 Km. So the average speed is roughly 544 Km.
The best day to arrive at Singapore is Friday and it would be best to avoid Monday, as prices are on average 82.85% higher than on Friday. (Average prices, based on 2987049 datapoints.)
We have a lot more statistics for flights SQ 148 and between Singapore and Bandar Seri Begawan.