https://www.techradar.com/news/nikons-new-mirrorless-cameras-will-be-called-the-z6-and-z7

With the official launch of Nikon's new mirrorless camera just over two weeks away the rumors are coming thick and fast, and the latest is that there will actually be two new cameras announced, and they'll be called the Z6 and Z7. 

According to NikonRumors.com, the Z6 will be a high-speed, low-light model with a 24MP full-frame sensor, while the Z7 will be a high-resolution model with a 45MP full-frame sensor.