However, We have some information from PMK with this issue that PMK said :
For the glass 6601215 first time we set STD on this glass around +1 mm and -2 mm at the year 2015
For the glass 6601215 first time we set STD on this glass around +0.0 mm and -1.5 mm at the year 2016 (February)
Then, PMK said on next batch of both parts they will control STD in tolerance +0.0 mm and -1.5 mm