He ran the alignment sequence. The mower’s guide wire sensor was off by 11 degrees. That explained the circling. The machine thought “straight” was actually a gentle arc toward Mrs. Almgren’s prized rose bushes. It had been slowly carving a spiral into her lawn for two weeks.
The 2021 production year introduced several firmware and hardware updates across the 300 Series (305, 310, 315X) and 400 Series (430X, 450X). Specifically, models from 2021 often feature updated charging algorithms and more sensitive collision sensors. If you skip the (Auto-check) for a 2021 unit, you risk voiding warranties and suffering from mid-season "ghost faults"—where the mower stops working for no apparent reason. automower serviceprogram autocheckrar 2021