This upcoming weekend is Salt Lake Comic Con and Brandon is planning to be there all 3 days. He announced this on his site yesterday, but some signing times just got posted sometime overnight: https://brandonsanderson.com/salt-lake-comic-con-ldsppa/
Panel and WoB's
Brandon did some non-spoiler Q&A and then read the first little bit of The Apocalypse Guard. That audio can be found here:
https://goo.gl/qCtFfe
Thursday Signing Line:
Friday Signing Line:
Saturday Signing Line: