No, the functionality of the MySite cleanup job cannot be customized. You will need to implement your own custom code/system for cleanup if you need to extend the email notice or change the time period in which sites are deleted.
Trevor Seward
Office Servers and Services MVP
Author, Deploying SharePoint 2016
This post is my own opinion and does not necessarily reflect the opinion or view of Microsoft, its employees, or other MVPs.
Proposed as answer byKRISHANA KUMARSunday, September 18, 2016 4:55 PM
Marked as answer bydanceNdance4Tuesday, September 20, 2016 8:21 PM