Microsoft is in the process of further refining and reducing the cumulative updates that we currently receive. The first test has been started in the new Dev Insider 26120.1252. Everyone else will then receive these updates from the end of 2024.
Microsoft is trying to make updates even smaller and reduce installation time, especially when they are distributed in companies. These smaller updates are achieved by creating checkpoints. This means that only the changes to the previous update are installed.
If a Windows 11 was previously completed as “RTM”, the cumulative updates were built on top of it. The monthly updates then contain all the changes at the launch of the Windows version.
Now checkpoints are created. “This allows you to get features and security improvements over the latest cumulative update through smaller, incremental differentials that only include the changes since the previous cumulative checkpoint update. This means you can save time, bandwidth, and disk space.”
These cumulative checkpoint updates will be available at regular intervals starting in late 2024. The Service Stack (SSU) for Windows 11 24H2 and, accordingly, Windows Server 2025 (which are identical updates) can merge all checkpoints and only download and install content that is missing from the device.
“When the Windows 11 24H2 cumulative update is released as a checkpoint, the binary differences in subsequent cumulative updates are generated from the version of the binaries in the latest checkpoint rather than the RTM version. Therefore, these differences are smaller and can be applied more quickly on devices that are already synced with the latest cumulative checkpoint update.”
Let's wait and see how this will work in real life. Smaller downloads and less time for updates are always welcome. The only thing missing are updates that don't require a restart (hotpatching). But those are still to come.