Handle repeated last-minute interview reschedules

You’re a candidate interviewing with TikTok. You requested a China-friendly time slot and it was confirmed, but two days later HR moved it. The second time, HR canceled one hour before the meeting due to interviewer availability and asked to reschedule. A third slot is proposed, but you suspect it may slip again. How do you respond to protect your time while staying professional? Provide: 1) the exact email/DM you would send now (2–3 short paragraphs), 2) specific guardrails you’d request (e.g., 24-hour confirmation deadline, backup interviewer, double-confirm 4 hours prior), 3) a plan for negotiating time-zone windows and minimizing disruptions, 4) an escalation path if the third attempt fails, 5) clear criteria for when you would pause or withdraw from the process, and 6) how you’d interpret these events as signals about culture and operational maturity. What risks do you foresee and how would you evaluate whether your approach worked (leading indicators and outcomes)?