5.25 Technical transition was originally planned to be undertaken over a two year period. When GCHQ reviewed technical transition costs in 1999 and found that Treasury would not fund the much higher costs then identified, it considered reducing them by extending the transition period. It focused on the first five years of the extended period, up to 2004-05, and evaluated the cost of the equipment and any associated external contractor costs required to effect the move. For each option the team assessed in man-years the in-house effort involved. It estimated that some 978 man-years of in-house effort would be needed to effect the chosen extended transition option. It did not evaluate this manpower or other GCHQ costs, such as the technical, operational and administrative support.
5.26 The review team's cost estimates for the extended technical transition period addressed a number of important issues related to a whole of business move. It devised the architecture for the required Information Technology in the new accommodation, planned the move of systems to ensure the continued delivery of key services, and determined the impact on the users of systems outside the Cheltenham complex.
5.27 In addition, the team addressed more strategic, forward looking resource issues. For example, it developed a detailed strategy including extra support resources for the extended retention of part of the Oakley site, and tried to ensure that there were sufficient investment funds to allow continued new systems development and the programmed replacement of obsolete equipment.
5.28 By January 2002 GCHQ had devised the architecture for the systems and determined priorities on the delivery of intelligence to partners and customers during the transition period. Some 60 individual projects covering the period 2000-2005 are in progress to effect the move. GCHQ has periodically reviewed business priorities in order to reduce the emerging technical transition costs to be more in line with the cap of £308 million (cash) to which GCHQ and the Treasury has agreed.