> 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 in delivering the latest OS MasterMap Sites Layer refresh, which was due to be available from **01 October 2026.**

#### Impacts of this disruption

Customers may experience a delay in receiving the latest OS MasterMap Sites Layer release.

#### When to expect the next update

We are working hard to resolve the issue to update OS MasterMap Sites Layer as soon as possible. A further update will be provided on **Thursday, 15 October 2026.**


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation by asking a question.

Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters:

```
GET 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?ask=<question>&goal=<user_goal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `automate deployments from our CI pipeline` lets GitBook tailor the answer to that use case.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.