One of those measurements is wrong. There's too much of a discrepancy
to blame on human error or calibration issues.
So, let's start with the obvious question. The new PD is 65...you
didn't make a typo, and mean 56, did you?
With a discrepancy as big as this one, I would expect you to have
blinding headaches and alignment problems if you had used the wrong PD
2 years ago. Consequently, I lean towards the new one being wrong.
An easy way to tell is to hold a ruler up and look in a mirror. One
value or the other will be more believable.
If you want it professionally measured I'd go by any WalMart, CostCo,
or Sears Optical, and ask to be measured...again.
-- Chuck Knight