Unable to delete current or future dated rows from absence plan

Summary:

In an existing absence plan,I have updated additional rows with absence plan changes and now business don't want the change to be implemented.

Scenario :

1. Initial absence plan effective from Jan-2001
2. From Jan-2025 business asked for change in absence plan,this has been added by updating absence plan effective from Jan-2025.
3. Now the business doesnt want the new changes as of Jan-2025 and need to remove the updated row on Jan-2025
4. Problem statement : Im unable to delete the additional updated row from UI or backend and couldnt see anything from HDL for deletion of current absence plan .

Can someone please help out how to delete the updated effective records from absence plan and keep the initial effective date changes only,In my case i want only Jan-2001 effective date without end date in the absence plan