There's a bit of confusion here. The first post here refers to me being upgraded to Platinum and not knowing why. The latest on that is following a study of my account it looks like all the points I earned in recent Accelerate tasks (over the last 4 to 5 months) have counted as qualifying points.
The second post refers to a recent stay that I made at the HIX Beijing Airport Zone, where I didn't actually pay for the night upon check-out. The stay then disappeared from my account (usually it shows up as "pending") and a call to the call center resulted in the stay being immediately credited, and all Accelerate tasks being immediately updated.
Sorry for any confusion.