It is a bit of a crap shoot in that situation.

I just booked 2 tickets to ORD for mid Nov where the only confirmed segment was the SFO-ORD. Both 14 hour SYD flights were to be WL.

I picked days when C paid seats were at their lowest and PA waitlisted those. Came through in 24 hours which is pretty a much a record, as they often make you sweat until a week or so out.

Being a vacation I can be that flexible but know a biz traveller cannot.