This question has come up over and over again for at least a year and probably longer. So far, I have seen zero replies or data points to suggest that the ULR flights (EWR/LAX - SIN) have ever been eligible for SQupgrade. These flight often have several empty seats in PE and J, but I would imagine that SQ wants to keep the loading even and the J fare higher by disallowing bids to upgrade. Honestly, I am surprised that they have not cut this route yet, but it could well be in the works (I really hope not, because I love getting PE LAX-SE Asia for $1200 or less). If I am incorrect, please let me know, as I have a RT from LAX in a month, and would love an upgrade.