Why McLaren is the only Mercedes team without the latest power unit at Silverstone

McLaren is lagging behind in adopting Mercedes' latest power unit for the British Grand Prix, unlike Audi and Ferrari who have already implemented their upgrades. This delay comes as Mercedes introduced a new, more reliable power unit after facing several retirements this season. The implications are significant as McLaren's competitive edge may be compromised, especially given the critical role power units play in F1 strategy and performance. This situation highlights internal challenges McLaren might be facing in integrating the latest technological advancements.