Macau and Hong as SARs or part of PRC in the future

Currently Macau and Hong Kong are Special Administrative Regions (SAR) in the PRC. However, that is only supposed to be for a fixed term. I believe it’s 50 years for both to keep the same economic and legal systems.

When the fifty years is up, will China keep those two regions as SARs or abolish the borders and make them fully part of China, allowing unlimited immigration from mainland Chinese into them?

If it’s financially viable, China might keep them as SARs if they make more money as SARs (especially Macau with the casinos). For Hong Kong, they might keep it as a SAR if it continues to be a financial center.

However, I can see China abolishing the border with Hong Kong if the independence movement keeps up in order to allow Chinese citizens to overwhelm Hong Kong. Then Hong Kongers become the minority and Hong Kong becomes just another Chinese city. I hope that doesn’t happen, but we’ll have to wait and see.

But there is no unlimited internal migration between China’s provinces and cities either.

The PRC would do so if they wanted to ensure it becomes Chinese. Like the PRC is doing in Tibet and East Turkestan, they move Han Chinese in to ensure the Han Chinese eventually becomes the majority.