Originally Posted by
RobOnLI
You will have to pick up your bag in SIN which means you will have to clear immigration, collect your bag, go through Customs and then go to the departures level to check-in for your next flight to DPS.
And from a timing perspective, keep in mind that "go to the departure level" also probably means transferring between terminals with your luggage. Most of the airlines that fly SIN-DPS do not leave from the same terminal that UA arrives into, and (starting tomorrow) will potentially even mean having to get to terminal 4 which is a 10+ minute bus ride...