Dear Client,
It's nice to see your requirement for updating your existing google apps scripts as Google is continuously adding new features as well as deprecating a few features.
I have been working with Google Docs, Sheets, Forms, Calendar projects (on other freelancing platforms) that use a variety of cases using Google Apps Script. For example, fixing a google script that used Document List API that has been deprecated and retired by Google.
Steps to fulfill your requirement:
1. Please share the issues that you face and snapshot of errors popping up related to existing functionality.
2. If they are due to a deprecated / retiring API, Google does propose new alternate API's. After understanding the functionality, the Google script code will be updated.
Please feel free to discuss any queries and share further details.
Looking forward to work with you on this project.
Sincerely,
Sohail
[FazlRabbi Tech]