I don't know what if any of these things matter to this calculus, but FWIW I have PM and the flight has been schedule changed.

I am booked RIC-JFK-SFO and back. Based on the flight load, I think I have a high likelihood of being upgraded to D1 on these flights.
On the outbound, there is an RIC-ATL-SFO that is a little better schedule-wise - is there a way without paying fare difference to say I only want to do this flight change if I get cleared into First at the 5 day mark?
On the return, there is a flight that goes SFO-ATL-RIC that leaves a little later than my current flight, and being an A330-300 instead of the 767-300 has a slightly better first/d1 seat. Is there a way to say if when I get to the airport (since this flight leaves later than my current one but both leave after 10pm and the differences are slight, I don't need to know before I get there) switch me to this flight if I clear into first?