On Tuesday, April 2, 2019 at 4:52:08 PM UTC-4, wrote:
There is some confusion over the start time. The email I got from the FAA said 7pm EDT (6pm CDT, 5pm MDT, 4pm PDT). The SSA page says 5pm PST, which fits - but we're not on standard time any more.

I heard directly from David that it is at what we today call "7pm central".