1. To upgrade to the new dynasty, only two landmark buildings corresponding to the times need to be built. This is two different lines from the upgrading of the times. You can even upgrade the era to level 4 first, and then slowly build landmarks to upgrade the dynasty level.

2. Detailed explanation of China dynasty mechanism in Imperial Age 4: Dark Age-Tang Dynasty, Feudal Age-Tang Dynasty or Song Dynasty, Castle Age-Tang Dynasty or Song Dynasty or Yuan Dynasty, Imperial Age-Tang Dynasty or Song Dynasty or Yuan Dynasty or Ming Dynasty. Except for the dark ages, China has two landmarks that can be built in every era. The first landmark is used to upgrade the era, and the second landmark is used to switch dynasties.