This study is centered on one English language arts (ELA) preservice teacher's development of her critical pedagogical discourses (CPD) with the contextual discourses of a school placement for preservice teaching and later shift to a full-time teacher before the placement was complete during a pandemic and in the midst of implementing online learning. Data is drawn from a 4-month interpretive qualitative case study that included classroom observations and semi-structured interviews. The objective for this study included how a preservice teacher uses their beliefs and identity about instruction amid changing contextual discourses in a pandemic and with a lack of mentorship. Discourse data analysis demonstrated that the CPD acted as a filter in her identity, beliefs, and dialogic instructional practices and to what extent they aligned or were compartmentalized in the classroom. Additionally, due to an abrupt shift from the preservice teaching placement to a full-time teaching position in a different district, it left her without a mentor classroom teacher. This study suggests that the teacher education programs and school districts should provide supportive mentoring opportunities for preservice teachers when they experience such displacement and are required to fulfill both job and university courses' expectations. This study indicated that such an unanticipated alteration in contextual discourses created a set of circumstances that primed the preservice teacher for a quicker departure from dialogic practices toward monologic practices. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]