From Apple website:
About 5G and Dual SIM
In China mainland, 5G is supported while using two active lines in Dual SIM mode on the line that’s using cellular data. Additionally, in China mainland, while using Dual SIM with 5G, 5G Standalone isn’t available. In Hong Kong and Macao, 5G isn't available in Dual SIM mode on iPhone 12 models.
點解會有呢個分別??
![](https://cdn.lihkg.com/assets/faces/normal/wonder.gif)