I had previously had no issues with what you are trying to do, but on my most recent swing through SIN about a month ago, with an overnight stay but well under 24 hours, UA refused to check my bags through and told me that SIN has a new policy that requires your to collect your bags if your layover is more than 4 hours. Sounded all wrong to me, but was nothing I could do at the time.

As it turns out, I was happy that I collected my bags there as some items were stolen out of one of them and that eliminated the second carrier as a suspect in the theft. Now it's between TSA and UA. We'll see how that one sorts itself out...

If you call and get a firm answer on this "new" 4 hour rule, please post and let us know.

TJ