AWS Cost and Usage Reports (CUR) with the "Overwrite Existing Report" option and Report data time granularity "Daily"

When using AWS Cost and Usage Reports (CUR) with the "Overwrite Existing Report" option and "Daily" time granularity, the behavior of folder creation and deletion is as follows:

The folder for the next month (20250101-20250201 in your example) would typically be created on January 1, 2025, not on January 2, 2025. AWS starts generating the new report for the next month at the beginning of that month.

Regarding the deletion of the previous month's folder (20241201-20250101 in your example), it's important to note that with the "Overwrite Existing Report" option, AWS does not create new versions of the report. Instead, it updates the existing report files in place.

In this case, the 20241201-20250101 folder would not be deleted. It would continue to exist, but its contents would be overwritten with the latest data for December 2024 until the month is finalized. Once January 2025 begins, AWS would start writing to the new 20250101-20250201 folder, leaving the December folder as is.

It's crucial to understand that with the "Overwrite Existing Report" option, you will only have the current month's report and the previous month's finalized report available at any given time. AWS does not maintain multiple versions of past reports when this option is selected.
Sources
Understanding your report versions - AWS Data Exports
Creating reports - AWS Data Exports