Looks like I was impatient! My application date is Dec-01-2019, and I received conditional approval for myself and my daughter just today (Aug-11-2020), so looks like processing time is somewhere between 8-9 months.

Maybe relevant as a data point - both myself and my daughter applied as US citizens; whereas my wife is a Canadian citizen with GC and she hasn't received her conditional approval yet (applied at the same time), though I'm hopeful it'll come soon. Not that it matters since no inteview slots are available in the US right now...