I just purchased 4 bags of 500, 6 bags of 600, and 3 lmb AM at Coop in NE.
The 500 is same dimension as my previous feed, but much lighter in color. No big deal I hope.
The 600 is about 1/3 smaller than my all the 600 I've ever bought. It's almost like they cut the original pellet 2/3 down, and one side is completely flat - it's no longer a rounded cube. I don't know why.
The LMB is much darker brown and again is about 1/3 smaller - it's now in a rounded cube like an oversized 600 pellet of it's former dimension. I fed it and the SMB and HSB seemed not to mind. I did notice it takes 2x longer to hydrate than my original LMB formula. The bag is no longer plain brown bag, it's now in packaging just like the 500 and 600.
I've been buying AM for 8 years and the feed dimensions have never changed. Seems that if they were going to alter the shape and size of the pellets, they would announce it in some manner, in order to manage their customer's expectations. I suppose this is to be expected, however, since AM generates such insignificant revenue for a conglomerate like Land O Lakes.
Has anyone else experienced different sized/shaped pellets?