I'm trying to solve the following issue.
I have "submit form" events in GA (google analytics) and the thing I need to do is to understand what was the first source and medium (from first session) of those events. The main goal is to know what campaigns or sources initiate "submit form" event that happens after a couple of monthes. I use Tag Manager + Universal analytics only so I hope to make implementation through them.
I see next solutions:
Create custom dimension and save first cookie referral. How to do it? Somehow do it with user ID and Client ID Somehow do it through ecommerce tracking It's important that I can't modify html code so we are going to use GTM and GA only. Please assist. Pretty sure that I'm not alone who is struggling with such problem.