Despite the significance of motivational regulation in the development of second language speaking skills, few studies have scrutinized its relationship with an emergent learning context. This study investigates how differently tertiary level English as a foreign language (EFL) learners exert autonomy and regulate motivation by proficiency levels to acquire speaking skills in the target language via a videoconference platform. Specifically, it contrastively examines student and instructor responses to several contextual factors specific to EFL speaking class, including synchronous online video platforms, native English-speaking instructors, and an English-medium instruction (EMI) policy. Employing a mixed method, it analyzes questionnaire responses of 340 students from two Korean universities and subsequent interviews with students and their instructors. These analyses reveal that the learners employed instructor feedback and motivational self-talk most commonly to regulate their motivation while acquiring EFL speaking skills. Although students across all three levels of proficiency showed increased vulnerability to the learning context, those of the lower two were found to be less aware of the significance of the imminent context created by EMI and videoconferencing. They also sowed stronger tendency to the strategies depending on their perceptions of the contextual factors than the advanced group. These overt differences in motivational regulation among proficiency levels were hardly problematized by the instructors. Notably, their views on peer interaction via videoconference were distinctly positive, displaying a clear difference from those of the students. A discussion of these findings follows to give insight into EFL speaking instruction in the emerging higher education context.