The Halton rumour just won't die. We (the RAF) own the whole estate outright having bought it for the princely sum of £112K around 1916 or so. As an aside I'm still eagerly awaiting the last ever Poirot episode which was recently filmed in Halton house.
Wittering on the other hand still has the "return to previous state" and resell to the original owners clause if it ever stops being used for a military purpose having been appropriated from the Burghley House estate.