Two agencies. Two years. The years the rest of the career is built on.
Every senior brand career has an early section where the person was, essentially, the one making the coffee runs and taking the meeting notes.
Mine was 2011 to 2013, split between FCB Ulka and Mullen Lowe. I started as a Management Trainee and left as an Account Executive. In terms of things I "led," the answer is: nothing that would look right on a leadership CV.
In terms of things I learned: how an account is actually managed. How a client conversation actually goes. How a brief gets written, killed, rewritten, re-killed, and finally shipped. How the sausage gets made — which is the single most useful thing to know in this industry, and the one you can only learn by being close to it.
Those two years didn't produce case studies. They produced the operating vocabulary that every subsequent role has been conducted in. Which is why they're on the site — not to claim credit, but to acknowledge that the rest of the work stands on them.