This means you might have to wait weeks or even months to get your hands on it, as Microsoft will only release the update for each device once it's safe to download.
However, as Windows Central reports, some PCs have been put on a compatibility hold by Microsoft while it investigates a blue screen error preventing users from downloading the update while a Thunderbolt NVMe SSD is connected. On the Windows Support page, Microsoft estimates a solution will be available in late November.
Besides this, the October update is relatively bug-free so far. At the time of writing, there are only three other known issues being investigated. Compared to the bug-plagued release of the May 2020 update, it's a big step forward.
These issues should not cause alarm to anyone who has already upgraded, as Microsoft has begun the rollout with devices it thinks will be least affected. The company is usually quick to release patches of any known issues, while throttling up the availability in this way ensures its servers aren't overwhelmed.
When will my device get the Windows 10 October update?
It's impossible to say for sure, but we wouldn't expect Microsoft to extend full rollout beyond the end of November. This is especially true considering Windows 10 security patches are released every month, so we'd be surprised if this leads to significant further delays.
There is a way to get the October update now via the Windows Insider Programme, but this will likely be an earlier build of the software which isn't as stable. Unless one of the new features will significantly change your experience with Windows 10, we'd encourage you to remain patient.
A handful of devices may not ever be eligible for the update, but this will likely be older hardware that's unable to fully support the latest feature. Provided Microsoft still supports for the version of Windows 10 you're running, it's fine to keep using.
For more information, it's worth checking the Windows Update Twitter page.