I am experiencing similar symptoms. I too recently replaced my battery. Resulting in No BAS ESP afterwards. Two weeks later I go to inflate my tires to 36psi from 28. The next morning after stepping into the throttle the BAS ESP light came on.

The BAS ESP light will turn off when the car is restarted but will come back on shortly after driving. When getting on the gas to pass or enter into traffic.

When the BAS ESP light comes on there is pretty much no passing power as if throttle is opening 10% I have my resonator removed too and it's whisper quiet when this happens. The transmission also hesitates to upshift when the light is displayed. Acceleration is slow till 5,000rpms then on the next upshift it will take off like a rocket throughout the whole rev range. As if it's going into some mode. Is any of this familiar?