From what I've read, China will attach a deportation order to every sentence, that is written like its to be completed after the prison sentence is over.
Since the Chinese government is intrinsically tied to their justice system especially when it comes to foreigners, the government can negotiate that the deportation order is executed and the sentence for example is commuted to a get out and don't come back ever.
Its in effect a shake down by the government of China.
I full expect that the one Canadian will eat a bullet and the bill sent to his family if Meng isn't set free, its a now we're serious moment.
This is a story of an American that was arbitrarily arrested and abused by China
https://www.cnn.com/2020/06/25/asia/...hnk/index.html
China does believe in hostage diplomacy. Its why Canadians should be encouraged not to go to China or reside there because they can simply dissapear and be sentenced in a behind closed door kangaroo court and then used as a bargaining chip.