234b/c

For the purpose of calculation of interest u/s 234B & 234C,it has been mentioned that interest will be calculated

from the due date i.e 1.4.2010 (A.Y 2010-11) to the date of determination of Income U/S 143(1)

I am facing problem of finding this date,

whether this date should be 30.9.2010 (A.Y 2010-11)

or

date of order U/S 143(1) (if the date of order u/s 143(1) is 24.8.2012)

so in this case the date of determination of income would be  30.9.2010 or 24.8.2012 (whatever  be the answer please give the reason for the same)
please sort out this problem as soon as possible.