I don't know if I just got extremely lucky, or if they've decided to be a bit more lenient in these last couple of days but...
I tried calling in to get two OC5s converted to a NC1-4 and a NC5 a few weeks ago, with no luck.
I just called the regular US support line again, mostly resigned to just getting two NC1-4s.
Asked, just in case, if I could convert my P830 and my 830T to one regular NC1-4 and one QP91 and said it should cost 60,000 points
Woman on the other end said no problem, went away for 2 mins, came back and said it was done.
I checked the app before even hanging up the call, and an NC1-4 and an NC5 were there and 60,000 points were gone.