Hmm,
I was thinking about this for more miles, but now I have another use.

I have a OW ATL-AVP I booked a while back with a UA ecert about to expire.
Outbound skyrocketed to 400+ even with lots of availability on both legs.
I can buy the same route on saturday morning for 165.

If the flight tomorrow afternoon is showing 9+ on both legs are my odds pretty good if I book the saturday 10AM and then use sameday change (24 hours) and leave Friday at 337pm?

So just to clarify if I book
AVP-EWR-ATL I cannot standby change to any other flight unless it has the same layover without incurring fees?