As they enter long-term survivorship, young adult cancer survivors grow into Active Architects of personalized digital support ecosystems, strategically curating resources across diverse platforms, from social media to specialized forums. Previous HCI research has shown how these individuals use technology through the early stages of their journey, to both support their needs and leverage their strengths. However, less is known about how technology might support survivors’ transition from self-management (task-oriented illness management) to self-advocacy, involving systemic, outward-facing action. This paper adopts a reflexive-interventionist approach, grounded in an interview study with 14 young adult cancer survivors who were diagnosed across childhood and adolescence. We show how their practices evolve across the journey, from family-mediated interactions during acute illness to autonomous curation, community stewardship, and advocacy. We articulate design implications for supporting ecosystem curation, accounting for evolving user expertise, and creating pathways that honor both ongoing challenges and developing capabilities.