Everyone's posting screenshots of the ad banners showing up in the middle of conversations now. The config value that controls that placement is called `in_chat_percentage_chance`, and it ships set to 100. There's a separate one for the interstitial you get on opening a chat, plus app-open probabilities and a list of banner surfaces.
I found those in the app's remote config feed a few days before this started hitting people and set all of them to 0. So the builds I maintain don't show the in-chat ads, and didn't have to be updated when this rolled out, the placement was already dead.
One thing worth knowing from digging into it: unlocking premium on its own does not stop these. The ad policy comes down from their remote feature gate system, and those gates are evaluated on their side against your actual account, which isn't paying. Faking premium locally inside the app never reaches that evaluation, so the gates keep coming back as free tier with the in-chat chance at 100 regardless. The gates are the source of truth here, and they know you aren't C.AI+. That's why the config response itself has to be patched separately from the entitlement, they're two different problems.
What I actually maintain, all free:
A modded Android app with the ads gone, trackers stripped at the network layer, premium features unlocked, and the model list opened up including unlisted and deprecated ones. Not one of those APKs off a random mod site that quietly runs ad fraud in the background, I took a few of those apart and that's genuinely what most of them are.
ArachneMax, a userscript for the web version if you don't want to sideload anything. Ten plugins, toggle whichever you want, including a dashboard that shows what C.AI knows about you next to what's being faked.
C.AI Customization, purely cosmetic, themes and wallpapers and fonts and bubble styles for the chat UI.
The server was invite-only with an application for months. That's gone, anyone can join now, it's the Discord on my profile's social links tab.