GSC Reporting - September 21, 2022

My GSC average position was incredibly steady up until September 2022. We moved a few positions up and down from day to day before then. On September 21, 2023 GSC says there was a search update that could effect results, and our GSC position bombed from hovering around 20 to around 50, with like 10-15 place swings day to day. Does anyone know what this update was?