Apple's OS X El Capitan has been on a faster tempo of preview releases than last year's Yosemite, perhaps signaling that the upgrade for the Mac will launch later this month or in September.
Although Apple's development process is opaque -- unlike rival Microsoft, it doesn't commit to a specific release date until just days prior, if then -- the timing of the six-so-far builds of El Capitan's developer preview have caught up to, then edged past, the timing of the same-numbered builds of 2014's Yosemite.
Last year, Yosemite debuted to developers on June 2, then ran through seven more builds, the last released on Sept. 15. Two weeks later, on Sept. 30, Apple issued the first of several "gold masters," or final code candidates.
Yosemite hit the Mac App Store, where users could grab it as a free upgrade, on Oct. 16.
This year's El Capitan, which Apple unveiled June 15 at its annual developers conference, was nearly two weeks behind Yosemite at its start, but caught up with the fourth build, released July 21, the same date on the calendar as Yosemite's No. 4 build.
El Capitan's preview build 6, issued on Monday, was two weeks ahead of Yosemite's sixth build on the calendar.
More notable has been the accelerated pace that Apple has used of late: El Capitan preview 6 came out just a week after No. 5, which in turn arrived less than a week after No. 4.
The faster cadence may hint at an El Capitan launch sooner rather than later. If Apple hews to the same general timeline as last year -- and with the faster beat of late -- it could issue a gold master as early as the end of August, and ship final code by mid-September.
That would match, more or less, the launch timetable of OS X Snow Leopard, aka 10.6, which shipped on Aug. 28, 2009. Snow Leopard may be an important comparison because it followed the much more significant upgrade OS X Leopard of 2007, and was billed as a polish on its predecessor, as El Capitan has been, with relatively few new features.
Apple's naming of El Capitan reinforced that idea. In 2009, when the Cupertino, Calif. company announced the impending release of Snow Leopard, an executive said, "We want to build a better Leopard, hence Snow Leopard."
In June, Craig Federighi, who leads OS X and iOS development, said something similar. "We wanted to build on the strengths of Yosemite. So the name came from within Yosemite," said Federighi as he unveiled the upgrade.
OS X El Capitan will be a free upgrade, as were its two forerunners, 2013's Mavericks and last year's Yosemite. Approximately 90% of Mac owners will be able to install and run El Capitan.