Time Trigger for existing records

Question

I have created a time trigger workflow to notify campaign owners (few listed users) once the campaign is ended after 1 day and final notification after 3 days.

• This is the workflow condition :
• created, and any time it's edited to subsequently meet criteria 

Workflow formula :

 AND( 
 OR ( 
 (OwnerId = '0050K000008w8dA'), 
 (OwnerId = '00528000003hxZN')), 
 EndDate = Today()    
 )

• Then created time trigger: 1 - Days - After - Campaign: EndDate 
• One more time trigger created for 3 days final notification.
• Then Workflow Action - New Email Alert - Added the template and selected  Owner in the Recipient Type.

I created a test campaign with End date today and checked the time-based workflow under Monitor and when I search with the workflow name it's showing up the Scheduled notification time. 

My concern is : 

• Will the existing campaign trigger if the end date reaches today, without a campaign being edited? If no, can you please suggest a solution for this scenario?
• There is a time lag between countries, how will the notification go if the time zone is different?

Answer 1

 AND( 
 OR ( 
 (OwnerId = '0050K000008w8dA'), 
 (OwnerId = '00528000003hxZN')), 
 EndDate = Today()    
 )

Based on your stated objective, you do not need (and shouldn't include) EndDate in your workflow entry criteria. You don't need this to use time-based actions. It sounds like you probably just want

 OR ( 
 (OwnerId = '0050K000008w8dA'), 
 (OwnerId = '00528000003hxZN'))

Will the existing campaign trigger if the end date reaches today, without a campaign being edited? If no, can you please suggest a solution for this scenario?

No, it will not. You can export all your existing Campaigns and perform a zero-content update with the data loader (just run an update on a file with no content except the Id) as an easy fix to get the workflow to fire and enqueue its time-dependent actions.

However, as written, your workflow rule won't fire on updates that don't change previously non-matching records to meet your criteria. You may want to change the entry criteria to allow updates other than updates to meet criteria to allow workflow entry, perform the updates, and then reset the criteria on the workflow.

There is a time lag between countries, how will the notification go if the time zone is different?

Per Considerations for Time-Dependent Actions and Time Triggers,

Salesforce evaluates time-based workflow on the organization’s time zone, not the user’s. Users in different time zones might see differences in behavior.

Answer 2

-Will the existing campaign trigger if the end date reaches today, without a campaign being edited? If no, can you please suggest a solution for this scenario?

No. You would need to edit/update all existing records in order to get the records queued. Workflow rules are not applied retroactively.

There is a time lag between countries, how will the notification go if the time zone is different?

The workflow rule should work correctly; the calculated values are in GMT. They'll get the notification at the correct time.