https://wccftech.com/macos-mojave-10-14-1-beta-3-released-to-developers/

Apple has seen fit to release the beta 3 of its upcoming macOS Mojave 10.14.1 update to developers. the update arrives a week after the company seeded the second beta an two weeks after the company rolled out its big macOS Mojave update to the public. If you’re a developer and interested in giving the new beta a go, here’s what you need to know. Let’s see some more details on what the new beta has in store for users.

With macOS Mojave, a new method was introduced to install the updates. After the initial beta has been installed on you supported machine using the appropriate configuration profile from the Developer Center, additional beta builds can be downloaded through System Preferences and then select “Software Update”.