Having worked in telecommunications and IT for over 25 years and done many large corporate moves, I am ASTOUNDED to learn that some equipment had to be moved 'live on the night'. You always buy new for Day One and then move the stuff you have to move for Week Two and so on. That is Project Management 1.01
In fairness, most of the equipment that had to be moved live on the night was large pieces of machinery such as loaders, hi-lifts, aircraft tugs and aircraft. Thats's not really the sort of stuff you can afford to duplicate. The majority of computer systems and comms had been in place at T5 months before the actual move date.