No idea what conclusions to draw . The readings on my vernier were on new line straight from the box.So it's best to ignore the stated breaking strains and just go with the stated diameter then.
I've been using the 0.36 and 0.41 for pike, not changed the line for a good few seasons, but I does seem like it can develop a slight oval shape with use - so that might explain the readings on your verniers?
But another "problem" is whether the line is the same, or fake, or that they've just changed the livery.
This (below) is my box, which looks quite different to the box shown on Dave Lumb's website (I am not inferring that Dave's is wrong in any way, am just pointing it out)