Changing the Offline Access Period for Sensitivity Labels

One of the settings for sensitivity labels governs how long items protected by a label remain accessible (including offline access) before reauthentication. The default is 30 days, which is a good balance between security and avoiding users having to constantly reauthenticate to open protected messages and files. If necessary, tenant administrators can change the validity period to be anything from 0 to 65535 days.

https://office365itpros.com/2025/10/14/offline-access-validity-period/