DDM profile for Software Update — MajorPeriodInDays not applied correctly under intune management.

Hello everyone,

I would like to report an issue with the behavior of Declarative Device Management (DDM) Software Update deferral logic when macOS devices are managed via Microsoft Intune.

Specifically, the MajorPeriodInDays parameter does not appear to work as expected. Major macOS updates are not offered to devices even after the configured deferral period has fully elapsed.

Under DDM, major updates never appear even after the expected deferral window passes.

If MajorPeriodInDays is removed or reduced, the update becomes visible immediately.

Legacy MDM with the same value behaves correctly.

This suggests the DDM implementation is calculating the deferral relative to something other than the official major release date (potentially the minor release date).

If any Apple engineers or community members have insights into how DDM calculates major update deferral timing — or if this is a known issue — any guidance would be greatly appreciated.

Happy to provide logs or additional details if needed.