The plaintiffs are represented by Andre E Jardini of Knapp Petersen and Clarke. The case is Pilgrim et al. v. General Motors Company LLC, case number 2:15-cv -08047 in the U.S. District Court for the Central District of California.
Knapp Peterson and Clarke
550 N Brand Blvd Suite 1500, Glendale, CA 91203
Phone: (818) 547-5000
Fax: (818) 547-5329
(FROM THEIR WEB PAGE)
You should contact Knapp Peterson and Clarke at the above address/number.
There was another article where GM blamed gasoline and the owners not breaking in the engine properly. With both my Z06s I was very diligent following the break in procedures. I don't believe I have any issue (25k), but then I am not sure of the symtoms (if there is any).