I have not heard of that one until now.
It does hit pretty close to two others I know of though.....
Do you have a scanner? If, so, can you please send me a scan of the broadcast sheet? Also, if you have not done so yet, can you please look inside both front seat backs for extra broadast sheets?
The date is the Scheduled Production Date (spd) it is the date they hoped to built the car, there is no way to know the actual build date. With your broadcast sheet info I can give you a rough idea how far out of sequence they were based on other broadcast sheets I have here.