Linking to Custom GPTs & Mobile Apps Not Implementing GPT Creator's Model Preference

Hey all!

Kind of a two-parter here:

I remember that the URL to GPTs used to include an optional model parameter, but it now automatically reverts to the default URL even if you include it, the parameter having no say on the model picked.

I say that because I noticed that the mobile apps (at least on Android) no longer revert the user to the GPT Creator’s preferred model for the GPT if their device’s default browser forwards the link directly to their downloaded ChatGPT app.

Even with getting my 4o GPT working correctly with 5.1 Instant, any link to it on mobile when an app is involved still defaults it to 5.1 Auto (even with 4o or 5.1 Instant set to preferred).

Is there a workaround for this to get this feature working again consistently across the board? Otherwise, it only works properly when they don’t have a ChatGPT app. Not sure why they would remove this feature from the app, as it used to choose the correct model even without the URl parameter…

Thank you in advance!