Originally Posted by
Pontius Navigator
It occurs to me that if the OP could identify them as Growlers it was not dark but twilight and technically not night flying.
Sorry, to be clear, the photo I took was on the early fly past.... Night then set on the city, and it was pitch dark at the time of the next flyby. It was advertised that it was the same aircraft, so you're right. I assume it was the Growler, however ... I'm pretty sure it was. They flew by at 19.04 to signal the start of the fireworks.