When/Will One Country Two Systems End?

Hello, I'd like to first say as someone who is not Chinese and well-versed in the theory surrounding one country two systems, I'm asking this more for educational reasons.

From my ignorant perspective I understand the important practical usage of the policy regarding the handing over of Hong Kong and Macau, and hopefully soon Taiwan, into the control of the PRC. If, like many Ultras and Maoists wanted, the PRC had immediately brought the former colonies, with highly entrenched and developed capitalist systems, under the direct control and supervision of the CPC, than most likely the UK and Portugal wouldn't had even agreed to let them go, or if they did would immediately instigate color revolutions and mass violence. It was necessary, if undesirable, to maintain stability and social cohesion between the economies, west, and peoples of the former colonies by allowing a degree of independence and separation between them and the PRC. This is why the same policy is directed at the eventual reunification of Taiwan.

(As well its so hypocritical that the west demonizes China over its handling of Hong Kong given that China has been extremely lenient and hands-off compared to most governments, especially western ones, faced with the same situation of gaining control over new territory with a completely different, and opposed, economic model. We only have to look at the disastrous and quick implementation of decommunization to see such hypocrisy).

But will the policy end? And if so what are the preconditions which must be met in order to change the policy? Essentially, when will the PRC abolish the privileges Hong Kong and Macau posses and directly incorporate them within the economic and political system of the PRC? When will the CPC gain complete control over them? For many like myself I actively look forward to this day, to see the full freedoms the PRC grants given to the people of the former colonies. But what must be done in order for this process to begin? Is it a gradual process which has been actively taking place since reunification, or will it take place more rapidly in the future?

Again, I think China has bigger problems to worry about then this, and I believe the policy is itself correct and necessary. So I'm not proposing Xi must press the socialism button on Hong Kong now or else he's not a real comrade. Rather, I'm curious as to how this entire situation is to be resolved, or how the CPC currently sees this happening.