Taiwan and the 144hr visa

This is definitely Timatic. Timatic is a database containing documentation requirements for passengers traveling internationally via air, e.g. passport and visa requirements and is used by airport staff and travel agents globally. Right at Timatic you will be able to see the detail that if you are traveling, for example, from UK to Taiwan via one of mainland Chinese airports, you are allowed to enjoy 144 hour visa free transit at that specific transit area being it Beijing, Shanghai, Guangzhou or some other... Thousands have used an itinerary that has Taiwan as a third country wile relying on 144 hour visa free transit and there is no reason why would not you too.