Answered by Borut | Jan. 04, 2024 00:22
Look, your first journey will be covered by 24 hour visa free transit and you do not need any kind of visa. In reality, if you do not leave airside, you do not have to perform any formality.
Your second journey has two mainland Chinese destinations in a row and you should be aware that when you have itineraries of this kind, you can only use 24 hour visa free transit or in other words, the time from your scheduled landing in Guangzhou until your final departure time from Beijing is not allowed to be longer than 24 hours!
So, if it is within 24 hours, you are fine and you will be again covered by 24 hour visa free transit and you do not need any kind of visa. Now, when you land in Guangzhou (I am talking about your second journey), the first thing you will do is to approach transit counter where you will apply for a temporary entry permit to be allowed to formally enter China because your next flight to Beijing is a domestic one. This application is a formality and free of any charge. It will be soon granted to you and you will proceed for Beijing.
Since you will arrive in Beijing by domestic flight, nobody will ask you anything, so you will have an overnight landside and after that proceed with your flight from Beijing to London. This is it.