It's all AU.

Krista was on her way to lunch with her husband Ianto; she stepped out of their house. When she turned around she was no longer at home, she appeared in the hub she was a bit confused.
"How did I get here?" Krista said with a surprised look on her face.

( Cut for length and irrelevence )

Slowly making his way down the hall, he peered into what looked like a dining room, scanning it for any sign of... well, he wasn't entirely certain what to expect here. Trouble, eventually. Of some sort. The Master wouldn't let him relax too long, just long enough to let his guard down, and then...

Jack shook his head, slipping into the room, keeping close to the wall, his back to it, so he could keep an eye out for anyone coming near him. He chose a table in a corner where the shadows were darkest, jumping a little when the server came up to hand him a menu, and set a glass of water on the table in front of him.

He took a long, grateful sip of it, watching the rest of the room. Not many people at the moment, and a few of them familiar. He caught the eyes of one of them as they looked in his direction, hesitating before smiling, a little hopeful, a little manic, and a lot broken.

It was going to have to happen sooner or later, Jack supposed.

Only so many roofs available to stand on, only so many places to get perspective, and too many of his analogues to be able not to coincide with them. After all, he'd already met his later self, his earlier pregnant self, and ...one that wasn't quite himself and he wasn't going to think too hard about that one.

Sooner or later, they'd end up on the same roof. At least it was flat and spacious, but his preferred gazing spot was occupied.

Moving forwards, he stood next to the man, mirroring his position, hands clasped loosely behind his back. "Nice coat for stargazing in."