That's platinum in every event of every campaign. Except one event I skipped in Aftermath, because...
For context, the highest platinum requirement in any of the other survival challenges is 70 zones, which takes around 10 minutes to complete. But Relay is a short and simple figure 8 track, so they thought 150 zones would be an appropriate final challenge for Aftermath. I tried it once, got to zone 100, then failed miserably. That's why I always dread survival mode. It's an interesting challenge, but it's so boring having to go through the slow speeds at the beginning. It's like having to play Desert Bus for a few minutes until you get to zone 30+.
Oh well... This event isn't going to beat itself, is it.
Zone 150 cleared.
And it only took 25 minutes, haha!