Unrecognized TIE Bomber Pilot Torso 76382 variant

Can anyone tell me when the back of the LEGO Black TIE Bomber Pilot Torso (76382) changed? I have watched multiple "unboxings" on YouTube showing TIE Bomber & Asteroid Field Set 75008 and TIE Interceptor Set 75031 and I have seen just as many posts showing the 2014 advent Calendar version. All show a short vertical line in the "small of the back". That said, I own 2 such figures... I also have 3 that are identical in every way except each is missing that small tick mark: 5 torso's, 2 variants. I can not find any information delineating the variants. I am an avid TIE builder (I have built every LEGO TIE craft along with a dozen plus custom craft) and this just plane irritating not to know. Thank you immensely in advance for any light you could shed on this!!!

Star Wars Minifigures (theme)

Kilmarnock228·9/27/2023

I admire your dedication, and wish I could think of any way to offer assistance. Brickset or Bricklink come to mind, but I’d imagine you’ve checked them.

Sienar Flight Systems Engineer·10/3/2023

Kilmarnock228 - I have tried Brickset and Bricklink. I check back every so often but at last check, there was nothing of help.

Thank you for the suggestions. I appreciate it!

What do you think?