KFC is a multinational restaurant chain. Their internal personnel management is divided into two pieces. One is the official contracted employees and the other is the laborers. Laborers are not considered formal KFC employees and cannot enjoy KFC's employee benefits, which means paying social insurance premiums. This type of personnel is usually students, half-work, half-study kind. Formal employees are usually those who have worked in KFC for a longer period of time. There are also those who have been recruited directly from the grassroots level.
The trainee assistants you mentioned are generally the formal staff that KFC openly recruits to the community. （
What you're saying is that KFC is openly recruiting regular employees from the community. (It takes a long time to get from the grassroots level to an assistant, and it took my master 4 years to get from cashier to assistant.) If you're recruiting for an assistant position, it should be a good idea to do so. You start out as a cashier, dishwasher, food preparation, general merchandising, etc. You have to be able to clean toilets too. Even cleaning the toilet must be done oh ^_^ assistant is mainly to assist the store manager to do store management, such as staff scheduling, recruitment, and so on the daily operation of the store work.
Talking about the work system, KFC as a catering company, as long as you work in the store, then it is inevitable to shift, especially the store manager, assistant store manager. KFC is an hourly calculation of working hours, the assistant and store manager at night to calculate the day's turnover, but also inventory. And so on follow-up work. Often have to work until 2 o'clock at night. So the double shifts you mentioned don't exist.
Since I've said that, I'll go into more detail. Regarding promotion inside, KFC as a chain, there are many internal positions, and the kind of job you mentioned with double breaks is also available. However, it is in the management department of KFC, which mainly manages the quality control of KFC and the management of each branch. The management system is very strict and very advanced (after all, it is a global enterprise), but the competition for that kind of position is very, very strong. If you really want to develop in KFC, there is room for advancement, but it will be very hard. Trainee assistants are basic KFC jobs.
Finally, I wish you success!