The public beta – sixth in a series that started in late July – was identified as build 14A388b, which matches the number assigned to the third ‘golden master’, or GM, released 9 October to registered developers.
Apple traditionally finalises its OS X code several days before official release. Last year, for example, Apple generated the last GM two days before launching OS X Mavericks on 22 October.
Apple will host a news conference 16 October, when it’s expected to introduce new iPads and announce the same-day availability of Yosemite. The company will live-stream the event.
Because Apple typically uses the last GM as the release build, and with only a few days to Friday’s event, developers who have upgraded to GM 3 probably have the final on their Macs and so won’t need to re-download and re-install it later this week.
Nothing is certain, however, since Apple is on unfamiliar ground: Yosemite was the first operating system that the company previewed to the general public since 2000.
Yosemite’s public beta weighs in at 5.2GB, slightly less than Mavericks’ 5.3GB, but still a massive download for those on slow broadband connections or whose ISPs meter their usage. The beta download process can be started from Apple’s website.
It’s unknown whether older editions, including 2012′s Mountain Lion, 2011′s Lion and 2009′s Snow Leopard, can be upgraded directly to Yosemite. Those editions can be upgraded to OS X Mavericks, however, hinting that Yosemite will also support the direct-migration paths.
OS X Yosemite will be a free upgrade from Mavericks, and available from the Mac App Store.