Datetime Calculation error - Type Mismatch - Converting out of range value \ Invalid

[MaazaMekuria]

I am not sure what is causing this error on date calculation but it is limiting me to only 24 days of difference between a start date and a future date. Changing the value of the variable from 30 to 24 and below will not cause error but anything above causes an error as image pasted below .  I have not experienced this before and I check the date value produced by the calculation and it appears to be perfectly valid for the Unix Date computation using Python TimeStamp functions.  Is there a limitation  on the function used in XLS forms for the amount of future date calculations?  Again it does not follow any logic here and I am not sure if  a parameter is missing etc.  

The sample spreadsheet is attached for your review.  I am using the latest connect executables.

[Neal_t_k · Accepted solution]

Try this out, for some reason it didn't like the unix epoch date calculation, but decimal date is working

[MaazaMekuria]

Thank you, Neal.  That is a neat workaround the problem.  This must be a bug that causes the error in the epoch calculation.