Hi! I'm in the exact same situation. I booked a ticket for PEK - WAW - JFK with Lifemiles for my mom departing tomorrow, but received an email yesterday from a LOT representative in their Beijing office saying she would be denied boarding. Did you email Lifemiles or just give them a call? I tried to explain the entire thing to the agent in Lifemiles but they didn't understand why this could happen, and LOT side said they would only talk to Avianca, not me. Already had a plan B but feeling so frastruated trying to reach both sides and get an answer.