I had one of those horror stories using an award ticket. I was travelling on my NZ passport with my son on a Norwegian passport, it was a same tick from Norway via CPH, PVG to Auckland. Due to bad weather on the Norwegian end we ended up missing our CPH PVG flight and were rebooked on an LH flight via FRA, the problem was with my Norwegian citizen 10 year old son, in 2015 Norwegians were not allowed into China without a visa, since we were no longer on the same ticket we had to go out collect our luggage and recheck it, it took a lot of fast talking to get them to allow my son entry to China and to exit.