Currently it says "cap of 25 messages every 3 hours" which means it wil resolve to $\frac{25}{3} = 8.3$.

This question will be resolved, on April 30th at 11:59pm, according to GPT-4’s reported queries permitted at the bottom of the chat API, rounded to 1 decimal point. If this number is no longer written at the bottom of the chat API because of UI changes, then it will be resolved according to documentation where this number is provided.
Credit to forecasting class which has a similar question.