If someone has created Sensitivity Labels with user-defined permissions, the following options were previously visible in Microsoft 365 apps (Word, Excel, and PowerPoint).
The modernized form is now similar to document sharing. The old form is replaced.
The rollout for Word, Excel, and PowerPoint in the Current Channel (Preview) started on July 15 (from version 2407 build 17830.20056).
Modernized user-defined permissions experience:
We’ve improved the user experience for selecting which users should have which permissions when a sensitivity label configured for user-defined permissions is applied to a file or when configuring standalone Information Rights Management through the Restrict Access feature.
The global rollout is planned for September. Depending on the release channel of the Microsoft 365 apps, the rollout will take several months.