Not really, gen is 13,22mm from bottom to crystal for all OP XXXIV based 42mm subs, including 959. Previous generation of 42mm subs that was based on P.9010 (like 682) have 14,5 mm thickness. One of the main reasons for movement change was to reduce the case thickness (at least that is what Panerai claims).
BR
do you have a reference point/link from where you have gotten your information?