We do not know exactly the architecture that sits exactly behind the UI, but it is based on gpt-4-turbo, which already has the an context window (32k) and knowledge cut-off (Apr 2023).
To access this version you need ChatGPT Plus. The free version uses gpt-3.5-turbo
If you want to show it to people, I recommend using the Playground with the different models to easily show the difference to your audience. If you’re preparing a presentation and want to use a chatGPT conversation, it’s always good to have it recorded just in case, so you avoid the chances of OpenAI’s servers being down or tha answer veering off course.