Post meals glucose

Hello, they just confirmed a few weeks ago that I have gestational diabetes and I am quite lost.I am not sure if the 2H post meals are since you start the intake or since you finish it.I am very slow eating 😔 and I can take half an hour quietly.
How do you do it?

2h since you start eating since at that time your body secretes insulin.

It is counted since you start as. They have told you, and the limits in pregnant women are stricter.