It’s the temperature. Wait until the first few above 70 days. I’m not far from you and it’s the same thing every year with various turbo cars/tunes. Stock is the only time they’ve felt consistent to me.
Should be fine. I plugged in o2 sensor, reflashed, drove for a few hundred miles and had all ready except for the same one you don’t. Just passed in Jan with the same background code. We’re allowed 1 not ready.