Can I extend the expiration period of retired leads?

No, there isn't any expiration period placed on retired lead records for your sales application. You must first retire a lead and then manually delete the retired lead by following these steps:

1. Open the lead.
2. Enter retire in the Action Bar and select the Retire action.
3. In the Retire Lead window, select a retire reason and optional comments.
4. Click Submit.
5. Search for and highlight the lead, and then delete it by clicking on the 'x' icon from the Search Results page.

You can create custom Groovy scripts, custom scheduled process jobs, or routines that check for leads that were retired for a specific number of days and delete them as per your specific sales requirements.