The My Nintendo Store store went offline yesterday in the UK, and will remain unavailable due to maintenance until tomorrow, Wednesday 27th July.
It follows the disappearance of the store in several countries across mainland Europe, where a similar maintenance message popped up admitting downtime lasting "a few weeks" (thanks, Nintendo Life).
Nintendo has not given any further details of the maintenance it has planned, or why it is happening now.
However, fans have pointed to the imminent release of Xenoblade Chronicles 3, due this Friday, 29th July, and the server issues faced by the US version of My Nintendo when orders opened for the game's Special Edition last month.
Here in Europe, "unforeseen logistical challenges" have led to a delay for the Xenoblade Chronicles 3: Collector's Edition, which will now only be available via My Nintendo post-launch.
Pre-orders for the contents of the Collector's Edition will become available in Europe in September, Nintendo said previously.