For your use case, I think the easiest way would be to use a combination of Google Apps Script and your Retool app’s integration. Before uploading new data to Google Sheets, you could write a script to clear the existing data, then use the Google Sheets API to upload the new file. As a side note, I’ve been working with date and time formats in Excel recently. If you ever need to separate date and time in excel, I found that using the TEXT function or splitting columns with DATE and TIME formulas works really well. It saved me a ton of time during my own project!