The Office365 probe (v1.1.4) lacks Pagination Support.
From looking at the Office365.log file, looks like the code is only making one call to this api:
https://graph.microsoft.com/v1.0/admin/serviceAnnouncement/issues
Therefore, only the first 100 records are returned to your probe.
Release : 20.3
Component : UIM - OFFICE365
Support added in office365-1.1.4-T1-20220114.080823-2.zip or later.