https://learn.microsoft.com/en-us/dotnet/api/system.workflow.activities.delayactivity.initializetimeoutduration?view=netframework-4.8.1&redirectedfrom=MSDN
DelayActivity.InitializeTimeoutDuration Event (System.Workflow.Activities) | Microsoft Learn
Occurs before the time-out duration starts.
event systemworkflow activitiesmicrosoftlearn