The codes I was referring were the ones the Chinese embassy release to you before travelling to China from a foreign country, you need to show those to the airlines flying to China but I noticed they didn’t scan they were just checking if it was green and if passport details correspond, one Chinese guy told
me a trick that if you keep the code page open without refreshing it will always show the same expiring time, I used the trick as my code had only 1 hour expiring and we had a big delay, another hour and technically I could
nlt enter china, still no clue why the Chinese embassy in Finland only gave me 15 hours validity