Jim, I'm wondering if my experience is typical to yours.
I brewed the beer Thursday, 4/26/18. Pitched yeast @ 21:30, at 50*. One pack of Wyeast 2206, dated 3/31/18, in Shaken not Stirred method (one Qt. wort). Which was started at ~12:00... maybe a bit late?
First airlock activity today (4/28) 09:00. ~36 hours.