Does anyone have any more details on what archives have been 'recently declassified'?
As far as I am aware, the overwhelming majority of wartime archives at Kew have been available to the public for quite some time, with the exception of some SOE and SIS files, so that surviving 'sources' and 'assets' and their descendants are protected. Air Historical Branch routinely ensures that RAF records are transferred to Kew on a regular basis, and thus hold very few original documents themselves.
Could this be German or other Allied archives?