Post-edit-window-edit: I retract "re-enabled autopilot" - . There was whole procedure required if there were residual airspeed discrepencies on all three sensors. e.g. Autopilot would only help if at least two were non-iced. AF447 may have had zero.
https://www.cbc.ca/news/world/airbus-gives-new-warning-on-sp...
http://www.aero-news.net/index.cfm?do=main.textpost&id=e7851...