> For the complete documentation index, see [llms.txt](https://docs.os.uk/os-downloads/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.os.uk/os-downloads/products/land-and-terrain-portfolio/os-mastermap-sites-layer/os-mastermap-sites-layer-known-data-issues-and-service-disruptions.md).

# OS MasterMap Sites Layer Known Data Issues and Service Disruptions

This page provides the details of known data issues and service disruptions impacting the OS MasterMap Sites Layer product.

## Live known data issues

| Data Issue Name                                                                                                            | Data Issue Description                                                                                                                                                                                                     |
| -------------------------------------------------------------------------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| Access Point features not intersecting the edge of the associated Functional Site                                          | There are **23** instances of Access Point features not intersecting the edge of the associated Functional Site, whereby the Access Point geometry is between 5m and 100m in distance from the referenced Functional Site. |
| Access Points referencing Road Nodes that do not exist in the latest OS MasterMap Highways Network – Roads product release | Currently, **103** Access Points reference Road Nodes that do not exist in the latest OS MasterMap Highways Network – Roads product release, although this error is often due to the timing of the releases not lining up. |

Once resolved, details of a known data issue will be held on the page until the next release of the product.

{% hint style="info" %}
To report an issue not currently listed here, please visit the ['Contact us' page on the OS website](https://www.ordnancesurvey.co.uk/contact-us/business-government/use-os-data).
{% endhint %}

## Service disruption – 05/10/2026

### Delay to scheduled OS MasterMap Sites Layer release

#### Disruption description

We are currently experiencing a delay to the October 2026 six-monthly release of OS MasterMap Sites Layer.

To ensure you receive the most up-to-date version of the product, we will be including some additional data in this release before publication.

#### Impacts of this disruption

As a result, the distribution of the October 2026 update orders will begin later than originally planned. We expect all affected orders to be processed and fulfilled by **20 November 2026**, which remains within our agreed service timescales.

#### When to expect the next update

No further updates will be issued regarding this disruption. Impacted customers will be contacted directly, and all affected orders are expected to be processed and fulfilled by **20 November 2026**.

We apologise for any inconvenience this has caused.


---

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