@Dearborn. John.
At first I thought the same.
I sorta felt that Doubleddie had a better idea how it happened.
It seems it only happens to every other vertical/odd numbered one. Which looks to be the ( field depth? If that /I'm making sense?)
I've only seen one with both side by side verticals partially affected.
2012 WDDR-004. Submitted by Tanner Scott.
I also wondered.
I have around 17+- 2021D with different verticals affected with different markers. From only one vertical and between up to five affected.
That seems like extreme out of adjustment a lot of times.
Maybe they can find out for sure.

