At the beginning of the model year the rear spoiler (J81) was not an OPTION so all early decklids do not have the cutouts.

When the spoiler was announced 10/69 Chrysler would've already had the engineering figured out & new "cutout" decklids ordered or in the "system".

there will always be exception (actual or imagined) but:

8/69 to mid-10/69 NO "cutouts"
mid-10/69 thru 11/69 EITHER
12/69 to 7/70+ "cutouts"