Texture offsets for phong and PBR textures work differently now. If you apply a phong texture and offset it, then do the same thing with a PBR texture, you'll end up with a different result. The PBR Y axis texture offset (but not the X) must be inverted in order to display the same area of the texture.

In a similar vein, when you scale a phong texture it stays centered. Scaling a PBR texture "zooms into" the top left corner of the texture, instead.

The attached images showcase both issues. In order to display the white part of the texture, phong requires a <-0.25, -0.25, 0> texture offset while PBR requires <0, -0.5, 0>.

As an example of why this is a problem, think of a chess game that has all its piece textures in a single texture atlas. Each tile on the board is a separate texture face, and you can choose which piece is in which position by adjusting the offsets for each face. Since PBR offsets work differently, if you want to add PBR support to this game you'll be forced to add additional code and use more memory to change the different offsets. As keeping both texture sets synced is a must, this means extra work for developing and maintaining this kind of code, while also adding to the extra memory load required to handle PBR textures in a script.

Making offsets and scaling work the same way for both PBR and phong would make this sort of scripting much easier.