The new overground CRC, which will fulfil a similar role as Buchan currently does, should be on-line by Q3 of 2005. No1 ACC and other units (eg SFC, TCW etc etc) are not expected to complete their move until 2012-2015, but my understanding is that they will move a lot earlier if feasible.
Domestic accommodation availability does not seem to be of great concern to the planners.
By the way, I understand the DHE are planning to build a load of FQs in the Lincoln area. However, as it will be done as a PFI, there no guarantee (indeed I would say it is unlikely) that the FQs will be built 'within the wire'.