Would expect it to be without stickers then. I assume it's the bottom red part:
https://www.ewrc-results.com/image/719315/
Maybe they use stickers also during testing, or have all bumpers without them and fit them first on the car. Anyway these kind of issues are best avoided by making it impossible to mount it, for example by not having it with them to the rally. Or by storing them completely different place and clearly marked. Commercial aviation and space industry have extensive and hard-earned experience of how things need to be make impossible to do the wrong way.
There was forecasted some thunder storm near Sunday stages today, looked very dark, not sure if anything came?
[WRC] Delfi Rally Estonia 2025