I believe cars spec’d with 19s from factory have a slightly lower spring, around 10mm based on the differences when fitting Eibach springs ( see below )
I haven’t seen anything to say the CS springs differ to the GTI springs, so maybe they are the same depending which size wheel you ordered from factory.
Eibach Sportline Lowering Springs – VW Golf MK8 GTI/GTD
Lowering range on standard suspension models (18″wheels):
25-30mm Front
20mm Rear
Lowering range on sports suspension models (19″wheels):
15-20mm Front
10mm Rear