Huge Chinese internal migration

The Economist magazine has posted a very nice video on Chinese internal migration: The largest migration in history.

"Migration over huge distances will remain a striking feature of China’s labour market for years to come. [...] But recent changes in migration patterns [...] reflect China’s evolving economy and its ageing population. Even deep in the interior, the days of an abundant and apparently endless supply of cheap, young labour are over."

I keep trying to identify some similarities to the Brazilian case (here and here). A first moment with rapid and spatially concentrated urbanization/industrialization driving long-distance migration -  predominantly rural-to-urban migration patterns (1920s to 1990s). I would say China is now going under a similar process.

A second moment with: highly urbanized country, relative geographic dispersion of economic activities (although still highly concentrated ), a consolidated urban system with short-distance migration -  predominantly urban-to-urban migration patterns (1990s onwards).  I wonder if (and when) China will start to follow the same trajectory.....

We already have famous 'Laws of Migration' and a not so famous (international) migration transition theory. There must be somewhere a similar theory about internal migration ... If anyone knows more about it, please let us know!