@Gary and all:
Hi Gary, 
thank you so much for your info. 
That´s interesting.
So you´re using the browser version, too. There should be no difference then.
All that led me to ask ChatGPT itself about what might be going on.
:
ChatGPT:
I totally get how frustrating that must be, especially if you’re in the middle of a conversation. Thanks for the detailed explanation—it helps a lot in understanding the issue.
You’re right that ChatGPT free tier users previously got downgraded to GPT-3.5 after hitting the GPT-4o limit, but now it seems that once you reach the limit, you’re locked out for a while instead of switching models.
Unfortunately, there’s no manual way to switch between GPT-4o and GPT-3.5 in the free tier. The model selection is automatic, and OpenAI hasn’t provided an option to force a downgrade to GPT-3.5 to avoid hitting the limit.
Possible Workarounds
- Start a New Chat:
- The message limits apply per session, so you might be able to start a new chat instead of continuing in the same thread. This won’t restore the conversation history, but it might let you keep using the service sooner.
- Use a Different Browser or Device:
- Some users have reported that switching to a different browser (or even using incognito mode) allows them to bypass the lockout temporarily.
- Clear Cookies & Cache:
- Try clearing your browser’s cache and cookies, then reload ChatGPT. It might let you send more messages before hitting the limit again.
- Check If GPT-3.5 Works in Incognito Mode:
- Open an incognito/private window and try accessing ChatGPT again after you hit the limit. See if it defaults to GPT-3.5 instead of locking you out.
- Use Microsoft Copilot (which also runs GPT-4 models):
- If you’re locked out and need quick access, Microsoft Copilot (formerly Bing Chat) also runs GPT-4 for free and could be a temporary alternative.
Unfortunately, OpenAI has been changing how limits work, so the old behavior (downgrading to GPT-3.5) might not be coming back. If this is a dealbreaker for you, upgrading to ChatGPT Plus ($20/month) would remove those restrictions.
Let me know if any of these work for you! 
Oh well… 
Update:
But there seems to be some new development (possibly
):
Note:
I had 2 discussions with ChatGPT today. In the 2nd one I asked it about the phenomon we´ve been discussiong here.
The 1st one was on a totally different subject.
Me:
You and I were discussing another topic today, in a separate thread. It´s called […].
I haven´t reached the limit for today in this thread, so I got no message whatsoever.
At the moment we are currently discussing the problem “Help with ChatGPT Issues” in this very thread, which is my second one today, and I just got the following message:
"You’ve hit the Free plan limit for GPT-4o.
Responses will use another model until your limit resets after 9:06 PM."
Do you see the difference? Today it doesn´t say “You’ve reached our limits of messages. Please try again later” but rather “Responses will use another model”.
And indeed your previous response was created by the model “4o mini”.
This time I didn´t get locked out any more. Perhaps the openai people, which are running ChatGPT, have changed their poilicy in the meantime?
ChatGPT:
Ah, I see! That’s super interesting!
It does sound like there’s been a change in OpenAI’s policy or how they’re handling the limits for free-tier users.
Based on what you’re describing, they seem to have moved away from just locking you out entirely and instead are now giving a more gradual transition.
Instead of completely blocking responses, they now revert to a lower-tier model, like GPT-4o mini, and allow you to continue your conversation with a different model.
This could be a recent tweak in how they manage the free-tier limits, which might be a response to user feedback or an update to balance server load more effectively. If that’s the case, it’s definitely a good improvement—still limiting usage but at least not locking you out entirely!
So, to summarize:
- Old Policy: Lockout with a message like, “Please try again later.”
- New Policy: Reverting to a different model (GPT-4o mini) and allowing you to continue chatting until the limit resets.
It seems like you’re able to carry on with a different model until the reset time. This is definitely a more flexible approach!
You’re right—this change could be very recent, and unfortunately, I don’t have real-time access to OpenAI’s updates. But it’s great to see the system is allowing more continuity. Hopefully, this is a positive shift for free-tier users!
Thanks for pointing that out! If this is the new norm, it’s definitely a big improvement. 
Well, it remains to be seen if the new and improved policy persits.
Many greetings from Rosika 