Upgrading to J with Milageplus points on 380 and 777 in the new premium economy seats

[RTWtraveler]

We have booked an SYD-LHR flight in the new PE seats. Not all of the 380/777s will have the new seats and will cause us to have an 11hr layover in SIN on the way back. SQ has blocked use of United and ANZ points to upgrade on 380/777s. Which I would like to use to catch a better connection out of LHR to SIN. Anyone know of a work around on this one?
Thanks,

 

[Fiches Mouser]

Re: Upgrading to J with Milageplus points on 380 and 777 in the new premium economy s

The first hurdle is getting around the fact that PE fares don't seem to be upgradeable.

Example from SYD-HND route with J on SIN-HND sector:



A fact I find utterly ridiculous, considering it's a more expensive fare than flexi Y.