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The rates still show in the app for me. (Same version as you have.)
They don't show in the list, I don't think they ever did on the phone, that is only in the car, only when you click on one for details. (Which makes sense, as if there are time of use rates you need to see that in the app for your planning, where in the car you are almost always looking for what the rate is right now.)
I also have v4.31.0-2552 but I can see Supercharger rates for locations far from my current location. Click the app's Location feature and then click the "lightning" icon (Chargers) and you should see stations near you. Zoom out in the map and it should populate with stations (you may have to wait a few seconds).
I'm in San Jose and I can see that the Ashland, OR site has 23 of 24 stalls currently available and that the cost is $0.35/kWh.