if EB1, when EB1 I-140 was approved, the PD was current, so in this case your CSPA age froze and stay frozen at the date (I-140 approval date - I-140 pending days = I-140+I-485 filing date) so it was your age in July 2007 (and it is the age on the I-485 filing date in this case).
if EB2 or EB3, when I-140 was approved, the PD was not current. It will be the next PD current date, say many EB2 became current in August 2008, so the CSPA age froze at (8/1/2008-I-140 pending days), but in your case the PD has never been current after I-140 approval (unless I-140 was approved before August 17, 2007), so your CSPA age is still growing, and cannot be calculated yet until next PD current date.
if EB2 or EB3, when I-140 was approved, the PD was not current. It will be the next PD current date, say many EB2 became current in August 2008, so the CSPA age froze at (8/1/2008-I-140 pending days), but in your case the PD has never been current after I-140 approval (unless I-140 was approved before August 17, 2007), so your CSPA age is still growing, and cannot be calculated yet until next PD current date.