It seems to be the case - I think. Every time I start playing with the spreadsheet trying to make sense of the mess, I am struck with how dumbfounded I am left.
The HO Cummins do not seem to be moving lately, and I wonder how much of that has to do with supply. The motors are manufactured in the US, then are trucked to Mexico, so it seems to reason that with the same truck shortage for everything else would impact that as well.
Maybe if we do a rain dance, in the rain, then turn 52 times with our forehead on a bat, followed by pulling unicorns out of the air we will figure out the rhyme or reason to the build sequence. Me personally, I think it all has to do with the line foreman having one to many the night before, then just walking in Monday morning and arbitrarily throwing darts at the D1 board and builds where the darts may fall. I figure mine will be built when all of the stars, planets, and USS Enterprises all align in a perfect row, but that is all dependent on Captain Kirk and the night he had!