The four Pilots awoke on stone beds in an isolated chamber, with Lah Rudania awakening on a plinth beside them. None of them could quite remember where they were or how they had gotten there - the last thing most of them remembered was joining the fight against Calamity Ganon, though Dinah was fairly certain they'd successfully vanquished the monstrosity.
Bo was frightened and angry and wanted to go home; as soon as he saw the only door in the room wouldn't open, he angrily fired a powerful Arrow of Light at it, successfully cracking it; but before he could do any more damage, Lah Rudania shared its power core with the door to enable it to open.
On the other side was a pitch-black cave; what little they could see into it seemed to be the result of a substantial cave-in, with serious rubble and debris making the path through treacherous. Ignatius summoned a torch around his hand, and Dinah drew the Sword of the Six Sages whose light could pierce the darkness; with this, they were able to navigate through to the other side safely.
They emerged from the cave onto a mountain top, with a piercing cold that rattled the bones; they did their best to keep themselves warm through it, with Bo navigating them to temporary shelters and Ignatius's fire keeping them warm, but their outfits rendered them unprepared for such chill, and Bo in particular was frozen half to death.
Once they finally descended the mountain to relative warmth, they tried to get their bearings; they couldn't recognize much in particular, but with the few ideas of what they could see, Lah Rudania was able to determine that they were somewhere on the Great Plateau, and that the mountain they had been on was Mount Hylia.
As he was unable to speak, though, he rushed ahead to lead the others to the edge of the Plateau so they could see for themselves - though when they did reach the edge, he stumbled right into a Bokoblin camp!
While the group was able to make short work of the Bokoblins, it was still troubling to see such creatures on the Plateau; this was supposed to be a safe place, a holy place. Dinah and Bo rushed ahead to the Temple of Time, which had partially collapsed, had been seriously worn down, and was currently inhabited by more Blins and a Wizzrobe!
These enemies, too, the party fought and vanquished, though Ignatius accidentally burned down some more of the temple that had survived thus far (oops!). But once they had a moment of peace in the temple, they started to worry and panic even more. Clearly a tremendous amount of time had passed - not only was the temple seriously ravaged by time and the elements, it had obviously been remodeled somewhat since they had last seen it; it had been decades at a minimum, potentially centuries, since they had fought Calamity Ganon.
Everyone struggled to take this in. Bo in particular couldn't accept that he was unlikely to ever see his family again, and walked off to get some time by himself.