Apple Software Update Deferral and Enforcement Calculator
Work out when an iOS or macOS update becomes visible to users under a deferral, and when a Declarative Device Management enforcement deadline forces the install. It covers softwareupdate.settings Deferrals, the legacy Restrictions delay keys (deprecated in OS 26, removed in 27) and softwareupdate.enforcement.specific.
Run Apple Update Dates
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What this is: Calendar arithmetic over Apple's documented keys, ranges, defaults and enforcement behaviour. Apple doesn't state the release date's time zone, so visible dates are calendar estimates.
Timeline
- 3 Nov 2026 · Apple releases the update
- 17 Nov 2026 · The update becomes visible to the user (14-day delay)
- 24 Nov 2026, 18:00 local · Forced install of 26.1 if the user hasn't installed it
- • If the user hasn't installed 26.1 by 2026-11-24T18:00:00 device local time, the device force-installs it.
- • If the device isn't running at that time, it enforces the update one hour after it restarts, or once it meets the required conditions such as minimum battery level.
- • The configuration only enforces a version or build that Apple's GDMF service lists as available; otherwise the device keeps it active but can't update.
- • Only 26.1 itself is installed: a patch version isn't installed when only a minor version is set.
- • Notifications: the device shows all enforcement notifications (Apple's default).
Requirements
- • softwareupdate.settings needs macOS 15.0 or later on a supervised Mac.
- • softwareupdate.enforcement.specific needs macOS 14.0 or later on a supervised Mac.
Who this Lab is for
Designed for
- Apple and Mac administrators using Intune, Jamf or another MDM
- Endpoint engineers planning patch windows
- Security teams setting update deadlines
Use it when
- Setting a deferral and telling users when an update will appear
- Choosing an enforcement deadline that doesn't clash with a deferral
- Moving from the legacy restriction keys to Declarative Device Management
A complete run, step by step
Pick platform and update type
iOS or macOS, and a major, minor or non-OS update. The deferral key depends on both.
Enter the release date and deferral
Choose DDM, legacy restrictions or none, and enter the days (1–90). Legacy keys default to 30 days when no value is set.
Add an enforcement deadline
Optionally enter TargetOSVersion, TargetBuildVersion and TargetLocalDateTime, and whether notifications are on.
Check the timeline
Read the timeline and warnings, then confirm the version is available from Apple and your MDM shows the declaration as applied.
What you will need
Prepare the following information before starting. Use measured evidence where possible; defaults are examples and should not be treated as recommendations.
Release date
The date Apple released the update, as YYYY-MM-DD.
Deferral
Declarative Device Management softwareupdate.settings Deferrals (1–90 days; the largest value across declarations wins), or the legacy Restrictions delay keys, which default to 30 days.
Enforcement
softwareupdate.enforcement.specific: TargetOSVersion, optional TargetBuildVersion, and TargetLocalDateTime as yyyy-mm-ddThh:mm:ss in device local time.
What the result tells you
Your report includes
- The deferral key that applies to the platform and update type, and the visible date
- The effective value across several declarations (Apple combines these keys with number-max)
- Enforcement deadline, notification behaviour and what happens if the device is off
- Warnings for deprecated keys, ambiguous legacy keys and deadline overlap
Notes on how this lab calculates its results
Calendar arithmetic from Apple's device management reference. Deferrals (softwareupdate.settings): CombinedPeriodInDays on iOS; MajorPeriodInDays, MinorPeriodInDays and SystemPeriodInDays on macOS; range 1–90; combined across declarations with number-max; updates appear only after the delay following release. Legacy Restrictions: forceDelayedSoftwareUpdates, forceDelayedMajorSoftwareUpdates and forceDelayedAppSoftwareUpdates with their delay keys, range 1–90, default 30, deprecated in 26.0 and removed in 27.0. Enforcement (softwareupdate.enforcement.specific): TargetLocalDateTime in yyyy-mm-ddThh:mm:ss local time; force install if the user hasn't updated; if the device isn't running, enforcement one hour after restart or when conditions such as battery are met; with Notifications false, only the one-hour warning and restart countdown show. Sources: Apple Developer documentation and the apple/device-management repository, checked 9 Nov 2026.
Calendar arithmetic over Apple's documented keys, ranges, defaults and enforcement behaviour. Apple doesn't state the release date's time zone, so visible dates are calendar estimates.
Model assumptions
- • The release date is the date Apple released the update.
- • Visible date = release date + deferral days, counted as calendar days.
- • TargetLocalDateTime is device local time; the one-hour notification offset ignores daylight-saving changes.
A macOS minor update with a 14-day deferral and a deadline
Situation
Suppose macOS 26.1 is released on 3 Nov 2026 (an illustrative date). A softwareupdate.settings declaration sets MinorPeriodInDays to 14, and an enforcement declaration targets 26.1 at 2026-11-24T18:00:00.
Result
The update appears to users on 17 Nov 2026. If they haven't installed it by 24 Nov at 18:00 device local time, the Mac force-installs 26.1. Only 26.1 is installed, not a later patch.
Use the result with engineering judgement
- Apple doesn't state the release date's time zone, so the visible date is a calendar estimate.
- Apple documents two keys as controlling the same macOS legacy delay in some cases without saying which wins; the calculator shows both dates.
- Apple doesn't document how a deferral interacts with an earlier enforcement deadline.
- It doesn't check whether Apple's GDMF service lists the target version, or whether your MDM supports these declarations.
Questions before you begin
Should I still use enforcedSoftwareUpdateDelay?
Apple marks it and the related forceDelayed keys as deprecated in iOS, iPadOS and macOS 26 and removed in 27, and points to the declarative softwareupdate.settings configuration instead.
What happens if the Mac is asleep or off at the deadline?
Apple documents that the device enforces the update one hour after it restarts, or when it meets the required conditions such as minimum battery level.
If I set TargetOSVersion to 26.1, will it install 26.1.1?
No. Apple states the system installs the specific version set and won't install a patch version if only a minor version is set.
Is anything sent to Apple or my MDM?
No. The calculation runs in your browser.
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