Currently the only option is to download all data. It would be nice to be able to export/download date using a date range or at least a start date.
That works for me, since I have all the data in SQL Express. Now all I need to do is append, which is much better than replacing the table every month to run my pivot table spreadsheet to match my electric billing schedule.
The move to Amazon Web Services required a rewrite of the data export feature to get around some limitations. I had to create the exports to be downloaded by month. http://support.teslafi.com/topics/626-data-export-no-longer-working/
This inadvertently helps this feature request. Unfortunately I cannot perform exports of more than one month due to the large amounts of data being processed.
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