Clarity on parameter of API

[PKhokhani]

Hello HubSpot team,
              I am using the event_email and subscription_changes endpoint in our integration. While making API calls, we are passing Start timestamp and End timestamp. So, we just wanted to know that these two params are following created(event_email) and timestamp(subscription_changes) field value that is available in the response of API?

[Jaycee_Lewis]

Hey, @PKhokhani 👋 Are these both custom properties? Can you provide an example request and response so that the community has additional details to work with, please?

Thank you!  — Jaycee

[PKhokhani]

No, these are not custom properties.  I have attached  screenshots for the request and response below,