Web & Mobile App: Switching to GPT‑5.5 Pro redirects to GPT‑5.3 mini

ChatGPT Bugs
1

Hi everyone,

I’m experiencing a frustrating issue with both the ChatGPT web version and the mobile app. Whenever I select GPT‑5.5 Pro from the model picker, the system silently routes me to GPT‑5.3 mini instead. This happens consistently, and I can’t seem to force the Pro version to load.

A bit of context: I actually came back to ChatGPT because I was unable to use Fable5 elsewhere – I’m trying to design a product feature that relies on the capabilities of the Pro model, but this routing behaviour is making it impossible to test anything properly.

Is this a known bug, or am I doing something wrong? I’ve already tried clearing cache, reinstalling the app, and switching networks – no luck.

If anyone has a workaround, or if an OpenAI staff member could clarify whether this is intended (maybe a load‑balancing fallback?), I’d really appreciate it. This is blocking my design work, and I’d love to get it resolved soon.

Thanks in advance for any help!

2

Hi there,

How do you know you’re getting routed to 5.3 and I’m assuming you have the ChatGPT Pro package at $100 or $200 per month?

When I select 5.5 and Pro mode it seems to be working correctly for me in both mobile app and web, on andriod , iOS, MacOS and windows 11.

3

I am using the $200 plan. After I ask a question using the Pro model, the thinking process ends very quickly, with only a brief flash of “Pro thinking.” And when the model finishes outputting the result, hovering the mouse over the retry button reveals that the model actually responded using GPT-5.3 mini. This only happened when I first upgraded the plan; everything is normal now.