ZOHO is recommending to complete all ZOHO custom work into V2 API, here is a detail from ZOHO:
We hope you are aware that the CRM V1 API has been deprecated, and its sunset date is on 31st December, 2019. However, the abolition of V1 API might affect your existing Deluge functions. To avoid possible data loss and ensure seamless operation of your Deluge functions, please take the following measures:
- Change all the V1 API URLs that are invoked using the Deluge tasks invoke URL, get URL, or post URL to their equivalent V2 API URLs.
- Change all Deluge's CRM V1 integration tasks used in your functions to their equivalent V2 tasks. The deprecated V1 tasks and their equivalent V2 tasks are listed below. You can find the help pages of CRM V2 API integration tasks here.