When does SQ start to clear waitlists?

[oxymoron1984]

Since the introduction of the new SIN-LAX flights via ICN, only waitlist business saver seats are available on all SIN-LAX via NRT flights through to Aug. I'm assuming that SQ is doing this to channel customers through the ICN flights. Will SQ open up seats on the flights via NRT, and if so, when do they start to clear in a case like this? I've been waitlisted for the past month... multiple phone calls through the call center and visits to the Ion office have not yielded results thus far.

To give context, I've just made individual same day SIN-NRT and NRT-LAX redemption searches and it looks like on both legs, Business Saver tickets are available on SQ 12 but only waitlist seats are available when searching SIN-NRT-LAX on the same day on SQ 12.