Microsoft has moved forward the deadline for Teams mobile users to update the app, warning that older iOS and Android versions will lose calendar access from October 2026. The change is linked to the retirement of Exchange Web Services in Exchange Online, and matters particularly for organisations managing app updates centrally.

Users have until the end of September to install a compatible version, while desktop and web Teams are unaffected. Automatic updates should handle most personal devices, but administrators must deploy updates to managed phones; Microsoft will disable Exchange Online EWS on 1 October 2026, with no exceptions after April 2027.