Fast changing environment put huge pressure on companies, which have to develop products increasingly faster in order to stay competitive. Change propagation in requirements engineering and life-cycle-management is a key competency to increase the efficiency of product planning. We propose a method using structural complexity management methods to achieve consistency between these two domains. Requirements modules and life cycle planning have been connected by matrix subtraction in order to identify changes in both domains. The result is an increased level of transparency of the regarded system. Additionally, traceability of change for supporting product planning in the early phases of a design process is enhanced.