This defect first manifest itself when opening a ppt with an embedded calc
spreadsheet. It was verified with an odp with an embedded spreadsheet and
further defined as an ods issue alone.

When saving a spreadsheet with combinations of numbers and dates and a formula
the formula displays as a date and the numbers get coverted to date format. When
opening up the columns for formatting the numbers can be changed back to general
numbers and they will display correctly. The formula needs to be re-entered
although the edit window displays it correctly. After making these changes the
data will display correctly. Once the file is saved and closed all the
formatting errors will show again upon re-opening. If the file is saved as an
xls and opened in Excel the errors are not present.

This issue was also verified in version 2.0.1.

I will attach a sanitized example document used to verify this defect.