4.4 From 1998 GCHQ started to consider the impact that reaching year 2000 might have on the integrity of its equipment and systems and gave Millennium compliance its highest priority. This decision had been endorsed by Ministers because of GCHQ's heavy reliance on information technology, the necessity to provide continuity of service to its customers and the nationwide concern over the potential impact of the Millenium on Information Technology systems. GCHQ allocated some 150 man years to this task and, as a result, there were relatively few resources remaining that could be committed to planning and estimating the costs of technical transition.
4.5 During the analysis of Millennium compliance, GCHQ realised the extent of the complex inter-relationships between its networks and equipment. These interrelationships had arisen due to the evolution of GCHQ's Information Technology systems over many years of operations. As a result, a simple move of equipment piece by piece, known as a "box move", into the new building would not be possible without unacceptable damage to continuity of services - in effect GCHQ would produce little signals intelligence for a two year period.
4.6 The new Project Director arrived in late 1998 and began to work on finalising the PFI deal and planning for the technical and non-technical transition. He created a Technical Board to oversee the planning of technical transition and held workshops to examine how the move of GCHQ's Information Technology systems could be accomplished. These workshops, building on the new-found understanding of the complexity of the interrelationships between systems, concluded that the transition would be significantly more difficult than previously thought. In October 1999 he established a new technical review team to undertake a detailed review of technical transition and generate a "credible and auditable" set of plans and estimates. In particular, the review team considered the impact of technical transition on the continuity of GCHQ's business and related security issues.