The Post-Purchase Report is separate from the Rebuy Report. This is not a breakdown of other post-purchase solutions from Rebuy: Shopify Thank You Page and Recharge Thank You Page. This report is static in it's datetime range and cannot be broken down to a day datetime.
Running a Post-Purchase Report
Step 1: Navigate to Rebuy Admin > Online Store > Post Purchase Offer.
Step 2: click on the 'View Analytics' button in the top right.