When GTM container loads

Hello, I would like to use GTM implementation which is described here – https://www.webtoffee.com/make-google-analytics-and-google-tag-manager-gdpr-compliant-using-a-free-plugin/.

I would like to ask one question before I do so – when exactly GTM container loads? Immediately after the user provides his/her consent? Or when the next page is loaded, now with GTM container?

Thank you very much for the answer
Andrea