China Post parcels actually go through an international postal union. The members of this union are postal companies or post ministry of different countries and most of the countries in the world belong to this union.

So parcels from China will go through many of the union member countries before arriving destination. the destination country post company is responsible for the delivery.

The route from China to a specific country changes very often depending on airline space, cost, economic and political situation of the route. It also depends on the import/export customs clearance speed of each country in the route, which are not controlled by China Post.

As You can see, the shipping condition outside of China is not controlled by China Post. So the delivery of international post parcel(not only China Post) is not so reliable, and sometimes might be extremely slow during rush season such as Xmas.

However, as it is a union of government companies, part of the shipping cost is financed by government. So its price is very economical. And in most time, the delivery time is acceptable.

As per our yearly statistics, from China to UK, fastest arrival time is 5 days(less than 5%). 30% parcels arrive within 2 weeks. 85% parcels arrives within 4 weeks and less than 1% never arrive destination.

Most items in the 1% lost parcel are illegal item or unsafe items such as battery, liquid,chemicals etc which are rejected or destroyed by customs officer. So if you follow the rule, your parcel will arrive sooner or later.

Hope this is helpful to you.