Apple last week released the first public beta of its upcoming upgrade, macOS 11, aka "Big Sur."
Previously, Apple had said it would deliver the public beta – a preview available to anyone, not just registered developers – in July. The Cupertino, Calif. company missed that month, perhaps signaling that it will issue the final code later in the year than has been its habit.
To obtain the preview, Mac users must enroll with Apple's beta program – Apple ID required – then install the upgrade (using About this Mac > Software Update from the Apple menu).
Apple warned customers against installing the Big Sur beta on production Macs. "We strongly recommend installing beta software on a secondary system or device, or on a secondary partition on your Mac," the firm said at the start of the beta program's terms. Users should also back up their Macs before upgrading to the preliminary Big Sur.
To dispose of the preview and return to the previous OS, customers must unenroll a Mac from the beta program and then restore the production-grade operating system using the Time Machine-created backup.
The first Big Sur public beta release rolled out considerably later than those of previous upgrades. During the past five macOS/OS X updates' summer previews – from 2015's El Capitan to last year's Catalina – Apple shipped the first preview between June 24 and July 9. (El Capitan and 2016's Sierra had their initial public beta releases on July 9 and July 7, respectively, while Catalina, 2018's Mojave and 2017's High Sierra appeared June 29, June 26 and June 24.)
The span between the first public beta and the final release ranged from 75 days (Sierra) to 105 days (El Capitan), with the average running slightly more than 88 days.
If Apple delivers Big Sur 88 days after its first public beta, the final would drop Nov. 2, more than a month later than the latest of the past five upgrades (Catalina on Oct. 7, 2019).
Apple has not specified a release date for Big Sur, saying only that the upgrade will hit the Mac App Store sometime in the fall. A November release would be unusual – four of the past five years, Apple's refresh reached users in September – but in a year when business and personal plans have been upended by the coronavirus pandemic, not a surprise.