Typically the discount days occur twice a year- already happened once this year. They post it on their clinic calendar: http://www.optigen.com/opt11_calendar.taf
The calendar shows limited months and it is not showing the next discount days. You can also often get discounts by attending one of the clinics posted in the calendar, just check before going. There might be a clinic close to you soon. You get a better price ordering online and when you do combos of tests, like PRA and RD/OSD.
There will be a "clinic" for the GRCA Natl Spec at Purina Farms at the beginning of Sept. All breeds can participate if you go to the clinic site. Only Goldens will be able to participate by sending samples direct to Optigen. So, if you are in the vicinity of Purina Farms ...
Optigen also usually holds a "discount days" clinic sometime in Sept. Last year it overlapped with the GRCA clinic, but this year our Natl Specialty is earlier in Sept.