On September 9, 2026, Apple shipped release candidates for all six operating systems due September 14, plus the Xcode 27 Release Candidate developers need to build against them. Apple’s own developer release index lists twelve builds across September 8 and 9, and their version numbers share almost nothing: macOS’s build does not even start with the same two digits as the other five.
Nothing in Apple’s developer release index is dated September 10, 11 or 12. The release pipeline Apple documents stopped on the 9th, three days before iOS 27 reaches the public on September 14.
| Item | Detail |
|---|---|
| RCs shipped | September 9, 2026, six platforms at once |
| Xcode 27 RC build | 27A266a |
| iOS / iPadOS 27.0 RC build | 24A435 (shared) |
| macOS 27.0 RC build | 26A428, a different train entirely |
| Same-day point release | iPadOS 26.7 (23H24), no matching iOS 26.7 |
| Nothing published | September 10, 11 or 12 |
Everything Apple’s release index dates September 8 and 9
Apple’s developer release index (developer.apple.com/news/releases/) lists these builds, in order:
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| Build | Date |
|---|---|
| App Store Connect update | Sep 9, 2026 |
| Xcode 27 RC (27A266a) | Sep 9, 2026 |
| iOS 27.0 RC (24A435) | Sep 9, 2026 |
| iPadOS 27.0 RC (24A435) | Sep 9, 2026 |
| macOS 27.0 RC (26A428) | Sep 9, 2026 |
| tvOS 27.0 RC (24J360) | Sep 9, 2026 |
| visionOS 27.0 RC (24M362) | Sep 9, 2026 |
| watchOS 27.0 RC (24R363) | Sep 9, 2026 |
| iPadOS 26.7 (23H24) | Sep 9, 2026 |
| Transporter 1.4.5 | Sep 8, 2026 |
| iOS 26.6.2 (23G90) | Sep 8, 2026 |
| iPadOS 26.6.2 (23G90) | Sep 8, 2026 |
Xcode 27 RC is the tool the April 2027 deadline points to
Apple’s own SDK requirement, announced the same day, tells developers to download the Xcode 27 Release Candidate to build against iOS 27, iPadOS 27, tvOS 27, visionOS 27 and watchOS 27. Apple’s release index gives that build a version number, 27A266a, and a date, but no changelog beyond that.
Apple’s own words, from the same September 9 post, read in full: “iOS 27, iPadOS 27, macOS 27, tvOS 27, visionOS 27, and watchOS 27 will soon be available to customers worldwide, which means you can now submit apps and games that take advantage of the latest Apple technologies and innovations like Apple Intelligence, the Foundation Models framework, design updates, new App Store features, and more.”
The one platform missing from the April 2027 SDK minimums
Apple’s April 2027 requirement names four platforms individually, not six. Its own wording: “iOS and iPadOS apps must be built with the iOS 27 & iPadOS 27 SDK or later,” “tvOS apps must be built with the tvOS 27 SDK or later,” “visionOS apps must be built with the visionOS 27 SDK or later,” and “watchOS apps must be built with the watchOS 27 SDK or later.” macOS does not appear in that list of minimums at all, even though macOS 27.0 RC shipped the same September 9 day as the other five release candidates, under build number 26A428, the one number in this cycle that shares no prefix with any of the others. Apple has not said whether that omission means a macOS app can keep shipping against an older SDK indefinitely, or whether a macOS-specific minimum is still to come.
Six release candidates, and not one shared build-number train
| Platform | RC build |
|---|---|
| iOS 27.0 | 24A435 |
| iPadOS 27.0 | 24A435 |
| macOS 27.0 | 26A428 |
| tvOS 27.0 | 24J360 |
| visionOS 27.0 | 24M362 |
| watchOS 27.0 | 24R363 |
iOS and iPadOS share a build number this cycle, but tvOS, visionOS and watchOS each carry their own letter after the same “24” prefix. macOS alone starts with “26,” a different train from every other platform shipping that day. Apple has not explained why its six 27-generation operating systems do not share a single build-numbering scheme.
An iPad-only point release, the same day
Apple also shipped iPadOS 26.7 (23H24) on September 9, with no matching iOS 26.7 release. Apple’s release index does not describe what iPadOS 26.7 changes, and it does not say why iPhone did not receive an equivalent point update the same day.
What Apple has not said
- Apple has not published a changelog for Xcode 27 RC, Transporter 1.4.5 or iPadOS 26.7 beyond a version number and a date.
- Apple has not explained why the six release-candidate build numbers do not share a single train.
- Apple has not said what, if anything, iPadOS 26.7 changes, or why it shipped with no iOS counterpart.
- Apple’s developer release index has nothing dated September 10, 11 or 12.
As of September 12, 2026, Xcode 27 RC and the six operating-system release candidates remain the newest builds in Apple’s developer release index, two days before iOS 27 ships publicly and six days before Apple Watch Series 12 reaches stores. Our event recap covers what Apple announced in the same week.
