I have to agree that the email notification was misleading. Just read it again:
"As a current licensed user of Photo Mechanic (with upgrades are good through July 2012), you have the option to preview the beta for free..."
This implies that you, the recipient of the email, ARE a current licensed user with upgrade good through July 2012, and therefore have the option to try the beta for free. It should have said "IF you are a current licensed user..."
Or two different emails should have gone out.
For me, I was due to buy a new licence anyway, so I did straight away. I have had very good value from the nearly four years of PM since I last upgraded my licence... time for payback
And ... dang ... it seems I missed out on the discount by being too eager