Here's another data point. I am a US citizen. I flew out of the country about 15 years ago. I plan on flying more for work and leisure. I flew twice domestically in the last 6 months.
Received new passport 09/03/19
Applied for Global Entry 09/03/19
Received Conditional Approval email on 09/08/19
Earliest interviews available in DFW is in November.

It was quite unexpected to have a 5 day turnaround.