Not at all frustrating. The production week on the body tag is commonly thought of as "when the car was built" and it just isn't. We had an 06E '67 Z/28 with an engine dated July 6 - VIN stamped, documented OE engine. Via Canadian records I learned the car was produced July 12, 1967, a bit later than the 06E date would have one believe.
I further believe there were certain periods during the production year when body tags were produced en masse and remained in queue for days or even weeks prior to fabrication of the body. All '69s produced in June have 06A tags. There are 13,000 06A Camaros built, far more than Norwood could build in a week.