From the Driving Standards Agency website;
30 July to 4 August
For essential IT maintenance work to take place we need to close down DSA's driving test booking systems. From 5.15pm Thursday 30 July to 8.00am Tuesday 4 August, online services to book or amend practical tests will be unavailable. Theory Test services will be available as normal. Please be aware that the Contact Centre will only be able to offer a limited service during the closedown period. Please call 0300 200 11 22 for general enquiries only. DSA apologise for any inconvenience caused.
Source: https://pt.dsa.gov.uk/tests/tests_E/pt/data_processing.asp
