There's something about WLP002 that makes it bottle bombish. Search the forum for a few threads on this. I too had issues with a batch, but it was a second pitch not the first so I can't say it was the yeast. I think it appears to stop fermenting, has a stable gravity, then decides to restart when given a bit of rousing and oxygen (aka when transferring to bottling bucket).
This is a picture from the Sam Smith brewery, but the concept remains the same. They spray the yeast from the bottom to the top to keep it floating about.
Here's a video from Black Sheep brewery, also a stunning Yorkshire brewery. I think the people in Yorkshire have it nailed down pat on making a solid beer no matter the brewery.
Open fermenter, wild spray. No worries about oxidation or contamination. Very solid beer.
Point being that perhaps the yeast needs a bit of massaging and rousing, and even maybe some shaking to get the proper behavior.