We explore the relation between firms’ internal skills and knowledge from past applications and the mechanism they use to adapt during an era of ferment and then to an era of incremental change in a new technological domain. We extend current research on incumbent firms’ success at facing radical technological change by studying dynamic firm boundaries of incumbents within the industry along a new technological trajectory. We use the concepts of problem, search, and solution from the knowledge‐based view and foundational view of knowledge recombination to develop our theoretical framework. We propose that preadapted firms—the ones with accumulated internal skills and knowledge from past applications that prove relevant by chance to the new technological domain—are more likely to choose internal technology sourcing during an era of ferment (than nonpreadapted firms). Subsequently, firms that choose internal sourcing during an era of ferment are more likely (than firms that source externally) to choose external sourcing during an era of incremental change leading to greater market acceptance for their innovation. Analysis of a longitudinal data set of 161 U.S. banks provides support for our hypotheses. The findings of this study indicate an important temporal dependency between internal and external sourcing, thus contributing to the sequential ambidexterity literature. Our theoretical framework provides support to the foundational view of knowledge recombination and contributes to the knowledge‐based view of the firm.