O1 models suddenly replaced with 4o - Plus user seeking clarification

Hello OpenAI team,

I am writing to report an issue I’m experiencing as a Plus subscriber. Recently, I’ve noticed that all my attempts to use o1 series models are being redirected to 4o models without any prior notification.

Issue Details:

Initially, the o1 models were only responding with "Got it! If you need any further adjustments or additional details, just let me know!"
After troubleshooting this first issue, I discovered that the o1 models appear to have been replaced entirely with 4o models
This occurred despite being a Plus subscriber and well within usage limits
No notification or explanation was provided for this change

I would greatly appreciate any information or assistance regarding this situation.

Thank you for your attention to this matter.