They dropped the appeal because they were never going to win it. Not because they have no case, but because it makes no sense to appeal to the fia for some decision made by that same fia.
That's a pretty simplistic view.
It is more likely that they're dropping their appeal in exchange for something... or greater bargaining power in 2022.
You don't back down from what even the FIA themselves admit was a shambles for nothing.
Shakedown is at 9 or 11 local time? YouTube link and official WRC has posted 11 local time but everywhere else it is 9 local time
[WRC] Delfi Rally Estonia 2025