HMRC have asked us to advise you that due to scheduled maintenance, the the CDS TDR (Trader Dress Rehearsal) Service will be unavailable for the period below:
From: 12:00 Tuesday 8th September 2026 To: 16:00 Tuesday 8th September 2026 (4hrs, UK time)
There will be a complete outage during this period. During this maintenance window HMRC will be refreshing the below data held in TDR: Trader personal, account, and licensing data, using data which will be copied from Production on Tuesday 8th September. *
*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.
HMRC wish to pass on their apologies for any inconvenience the period of downtime may cause whilst they undertake this important update, and appreciate your understanding.
Kind regards ChamberCustoms Team
Posted Sep 02, 2026 - 14:41 BST
This scheduled maintenance affects: ChamberCustoms Systems (Customs Declarations (SGS) - TDR) and HMRC Systems (HMRC CDS (Import/Export declarations) - TDR).