I may be reading the document wrongly, but it seems to be a procurement plan for contractors to look at redeploying resources: "these projects are known as Estate Optimisation projects and will be advertised in the OJEU [Official Journal of the
European Union]." As Halton and Henlow are on the same line in the list, might it be a question of how to accommodate the remaining units/personnel from Henlow at Halton? That would get perhaps avoid the Rothschild agreement/Crichel Down Rules.
Page 43 shows that a contract for "Site Appraisals for RAF Halton and RAF Henlow" has been awarded, with a value of £5,000, for completion by the end of May 2017 - that appraisal will presumably inform the next stage.