Originally Posted by
AKLifetimeFlyer
I believe there was a thread about KTN's vanishing from accounts after the website upgrade. Whenever I have an issue with my KTN not appearing on my boarding pass (usually during AS leg of partner award booking), I just have a check-in agent add the number. By the time I get to TSA, it is good to go. I always carry my global entry card so I have the number with me at all times.
That is my plan barring anything else. The lines at SEA can be nuts though so I may just go the non PreCheck route.