> 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/addresses-and-names-portfolio/addressbase-premium/addressbase-premium-known-data-issues-service-disruptions-and-planned-maintenance.md).

# AddressBase Premium Known Data Issues, Service Disruptions and Planned Maintenance

## Live known data issues

There are no live known data issues for AddressBase Premium at this time.

## Service disruption

There are no live service disruptions affecting AddressBase Premium at this time.

## Planned maintenance: 25 June 2026

### **Maintenance description**

A VOA resynchronisation activity is being undertaken to correct and align address data, improving overall data currency and completeness. The update is expected to introduce a higher than normal volume of changes (\~75 000 records), resulting in larger COU files for affected products.

The changes will be reflected in AddressBase Premium **Epoch 129** scheduled for release on **25 June 2026.** 

### **Impacts of the maintenance** 

Customers should expect increased file sizes and a higher volume of change records in the relevant release; no service downtime is anticipated.

{% 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 %}


---

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