When A Female Cat Is In Season Does Her Behaviour Change?

Yes, she will meow a lot more, and will take a position in which her rump is up, and she is almost laying down. It's just how they behave when they are in heat. If you get her fixed, she won't do this anymore. Hope this helps, good luck to you and the kitty.

She will chortle with more of a long, drawn out meooooowww, singing her little love song and do the dance with her hind end poked up in the air. She may stay up more at night and linger around the windows and doors. If she gets out, it is a certainty that she WILL be pregnant when she comes back home. Tom cats may start hanging around your house hoping to court her. They will start spraying urine around your house, car, flowerpots, etc... This can become really unpleasant. Unless you can provide homes for future kittens I would strongly recommend you get her spayed.

She may want to spend more time out doors and she may eat more

Maybe she will  just like people who in season.
But I only want to know if this IE in China?