Since retired 5 years ago, I haven't bought a DL ticket, but Ive been using plenty of miles for F tickets. I'm also lifetime PM. Now I need to do a simple overnight RT PDX-ATL in Sept. I'm only seeing 80,000 miles for an F ticket, so I'm thinking I might actually pay for the ticket. Two questions:

If I book a free coach ticket, it says I might get an upgrade. Is that a realistic expectation?

If I buy a coach ticket, it used to be that certain fares (e.g. Y) virtually guaranteed an upgrade at the time of purchase. Is that no longer the case?

I definitely do not want to take the chance of sitting in the back of the bus for such a long trip. Any advice appreciated. Thanks