HMRC has issued information regardign an upcoming outage to the CDS Trader Dress Rehearsal (TDR) service. The notification is as follows:
"We will be completing a maintenance update to the CDS Trader Dress Rehearsal (TDR) service on Tuesday 25th August.
The outage is expected to last 4 hours, beginning at 12:00 until 16:00.
During this maintenance window we will be refreshing the below data held in TDR:
- Trader personal, account and licensing data, using data which has been copied from Production on Tuesday 25th August.
- Refreshing UK/EU Tariff data, using data which has been copied from Production on Wednesday 12th August*
*Trader Dress Rehearsal is a sandbox environment and is regularly refreshed with Trader data and data from the Online Tariff on a given date, as such any CDS changes to Trader data in the live service or updates to the Online Tariff will not be reflected in TDR instantaneously.
There will be a complete outage during this period."
Posted on Tuesday 18th August 2026