Two interesting observations: The most recent utterances of the words "temporal pressure" (similar to the titles of these last two chapters) was in chapter 86 when discussing the Halls of Prophecy:

""The Hall of Prophecy," Minerva whispered. She'd read about that place, said to be a great room of shelves filled with glowing orbs, one after another appearing over the years. Merlin himself had wrought it, it was said; the greatest wizard's final slap to the face of Fate. Not all prophecies conduced to the good; and Merlin had wished for at least those spoken of in prophecy, to know what had been spoken of them. That was the respect Merlin had given to their free will, that Destiny might not control them from the outside, unwitting. Those mentioned within a prophecy would have an glowing orb float to their hand, and then hear the prophet's true voice speaking. Others who tried to touch an orb, it was said, would be driven mad - or possibly just have their heads explode, the legends were unclear on this point. Whatever Merlin's original intention, the Unspeakables hadn't let anyone enter in centuries, so far as she'd heard. Works of the Ancient Wizards had stated that later Unspeakables had discovered that tipping off the subjects of prophecies could interfere with seers releasing whatever temporal pressures they released; and so the heirs of Merlin had sealed his Hall. It did occur to Minerva to wonder (now that she'd spent a few months around Mr. Potter) how anyone could possibly know that; but she also knew better than to ask Albus, in case Albus tried to tell her. Minerva firmly believed that you only ought to worry about Time if you were a clock."

Next, near the end of chapter 89, Harry "turns away from Dumbledore" twice, almost as if there's a kink in time after explicitly mentioning "pressure":

Harry opened his mouth to scream out all his fury, and then closed it again. There wasn't any point in screaming, it wouldn't accomplish anything. The unbearable pressure rising inside him couldn't be let out that way.

'Harry turned away from Dumbledore and looked down at where the remains of Hermione Granger were lying in a pool of blood ... another part of him already knew that this event was real, part of the same flawed world that included Azkaban and the Wizengamot chamber and

No

With a fracturing feeling, as though time was still torn to pieces around him, Harry turned away from Dumbledore and looked down at the remains of Hermione Granger lying in a pool of blood with two tourniquets tied around her thigh-stumps, and decided

No.

I do not accept this."

Hypothesis: Something very strange just happened to Time around Harry, possibly involving a time turner, and things are definitely not as they seem.

It's almost as if someone is trying to manipulate Harry's reaction to these events, like when H&C tricks Hermione repeatedly. Fred and George are unconscious at this point, too. It goes without saying that Harry is probably an unreliable narrator.