Hi, @IniobongNkanga-8038
Do you want to set another EWS throttling policy duration shortly after the end of one EWS throttling policy duration?
There is currently no official Microsoft document on whether another 90-day EWS throttling policy duration can be set again immediately after the end of the duration.
As far as I know, when duration ends, you may have to wait 180 days before you can do it again through the portal.
More information can be found Self-service EWS throttling change – Mike O'Neill's Technical Blog (mikeoneill.blog)
Please understand that as a public forum support, we do not have higher privileges to add additional duration restrictions. Of course, you can request an additional increase in that limit through phone support.
More information can be found Get support - Microsoft 365 admin | Microsoft Learn
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