What's the difference between "Update Current" and "Save New" when saving a report?

Update Current will NOT create a new report. It will override a current report.
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On the other hand, Save New will create a brand new report.
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So if you have a report for 3 bedrooms, load it up, and change it to 4 bedrooms, Update current will override the 3 bedroom report while Save New will create a brand new separate report.