Brian hit on it. There were no other 06 weeks until 07A. Just one *long* 06A week.
So an 06A car can have parts dated til the end of the month.
Trans' did sit for a while. Not common to have one dated near the assembly date.
And the trim tag was not the scheduled build date but the build date of the body.
The BE rears were the shortage, which is what causes the body #'s on COPO's to be off from regular cars.