I need to create a service type based on the contact to which the Ticket is assigned and depending on whether it is a request, take a list of 3 events that will cover 12 hours before expiration and when it is an incident take a list of 3 events that will cover 4 hours before Expiry date
The idea is to use the same serivice type and that this is responsible for differentiating if it is a request or an incident and then start the correlated events.
Unfortunately there is not currently a way out of the box to have an SLA be dependent on a contact for which a ticket is assigned to. SLAs are driven generally by category and priority on a ticket. You may be able to accomplish this using CA Process Automation, but its not something we have documented, and is not something we can support as it would be outside of our scope. There may be some folks out here on the community who have been able to get this to work, and they may be willing to share their info with you.