If you want a cheap flight from Dundee to Beijing, you've got one airlines to choose from.
Beijing Capital Int. Airport is just one of the airports in Beijing. If you're not set on a specific airport, try changing your search from Beijing Capital Int. Airport to Beijing to see a broader range of flights – they might be cheaper. It usually takes about 18 hrs 40 mins to fly 7887 km to Beijing Capital Int. Airport.
There are about one flights to or via Beijing every week, so you have plenty of options.
You can expect accommodation prices to be higher at this time of year too. Last-minute deals do crop up, but it's best to book everything in advance to avoid disappointment.