We've now resolved the incident. Thanks for your patience.
The issue looks to have been caused by an unexpected spike in SQL database utilisation, this had a knock-on effect causing slow response times in the Portal and other web applications along with slow message processing. This is now recovering and we can see overall platform performance returning to normal.
We will continue to monitor.
We are currently investigating a performance issue with one of our resources that may be causing slow application performance and slower than expected message processing.