When I did my one trip since the COVID panic started in earnest, I sat alone in 3 A/B, and then had the last row that they sold in coach (31F) to myself.
The MSP-SEA trip on 5/5 was close to a "sell-out" under their social distancing rules, with about 70 pax on a 737-800.
I was looking at a couple of possible trips, and I noticed that they've "X-outed" seats in F that they are not selling. I also noted that on a DCA-DTW-SFO itinerary in the first week of June, paid F is only about $60 more than paid C+.