Today Apple released a new round of software betas for developers, unleashing beta 6 builds of iOS 12, tvOS 12, watchOS 5 and macOS Mojave 10.14.
Shortly afterwards, Apple also released new beta builds for public testers, which are equivalent versions of those released for developers.
Public beta 5 builds of iOS 12, tvOS 12 and macOS Mojave 10.14 were made available for its public testers, marking the first time an iOS 12 beta build has released simultaneously for developers and public betas on the same day.
Last year, iOS 11 reached 10 betas before the golden master released was issued. So with this in mind, at the rate of one new beta release every week, a rumoured Apple September event could take place in four weeks or so. If the event again happens on a Tuesday, that means September 4th or 11th.