I'd like a source on CPC officials saying they don't have a socialist economy yet. Their officials call it a socialist market economy, because that's what best describes it. Here's Xi Jinping, in 2013:

First of all: Socialism with Chinese characteristics is socialism, not any other “ism.” The guiding principles of scientific socialism thus cannot be abandoned. Our Party has always emphasized adherence to the basic principles of scientific socialism, but adapted to the particular conditions of China. This means that socialism with Chinese characteristics is socialism, not some other doctrine.

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In recent years commentators both at home and abroad have questioned whether the road pursued by China is truly socialist. Some have called our road “Social Capitalism,” others “State Capitalism,” and yet others “Technocratic Capitalism.” These are all completely wrong. We respond that socialism with Chinese characteristics is socialism, by which we mean that despite reform we adhere to the socialist road — our road, our theory, our system, and the goals we set out at the 18th National Party Congress. This includes building a socialist market economy; socialist democratic politics; advanced socialist culture; socialist civil harmony and ecology; all-around human development; the gradual realization of common prosperity for all people; a rich, strong, democratic and harmonious socialist modern state under the leadership of the CPC with economic construction as the center; adhering to the Four Cardinal Principles; insisting on Reform and Opening Up; and the liberation and development of the productive forces. It includes adhering to the system of People’s Congresses; the system of multi-party cooperation under the leadership of the CPC; the systems of national autonomy at the regional level and mass autonomy at the grassroots level; the socialist legal system with Chinese characteristics; and the basic economic system in which public ownership is the mainstay and a variety of auxiliary ownership systems develop alongside. These goals embody the basic principles of scientific socialism under our current historical conditions. Adherence to the socialist road demands that we fulfill them.

Capitalism is indeed not markets, but it is also not determined by simple ratio of private property to public, nor is a system with X% private and Y% public X% capitalist and Y% socialist. Dialectics rejects these frames of analysis as metaphysics. What matters is what is principle, what is rising and dominating the economy. In the PRC, the large firms and key industries are overwhelmingly publicly owned.

The private sector in China is about half sole proprietorships and cooperatives, and the rest small and medium firms. Despite making up a sizable portion of GDP, these do not control the economy, nor direct its trajectory. The basis of communist production is in large industry, not just collectivizing even the small firms before markets have centralized them. This does not mean it is necessary for private property to exist to develop socialized production, the DPRK is a good example of this (though they have special economic zones like Rason). However, it does mean that by maintaining public ownership of the large firms and key industries, socialism can be maintained. China's socialism is the socialism suited for China.

The problem with looking at simple ratio, is that this makes no analysis of how power is distributed, what tendencies are rising and which are dying away. This views production and distribution not as something that changes in identity as time moves forward, but instead as a substance in flux. In this way, it is metaphysical. When accurately contextualizing the relationship between public and private in China, it is the public sector that holds all of the power, that absorbs the private over time as the private grows and develops. Dialectically, China exists in the transitional state between capitalism and communism that we call socialism.

Harkening back to Cheng Enfu's diagram, they are in the developing and intermediate stages of socialism. They are not advanced in socialism, and likely will not be for a while. Their progress is thanks to socialism, however, built by Mao Zedong and the CPC, carried to today and interated upon as new conditions arise and new contradictions form.