Using Extended Thinking + web search does extend its knowledge beyond the training data cutoff point of Dec 2025 but (from my testing) seems limited to ChatGPT interface.

When I tried using the OpenAI gpt-image-2 API directly to create an infographic based on the results of the April 2026 London Marathon, it presented the image as if it were using up-to-date data but it clearly pulled the records from 2025 missing the fact that runner Sabastian Sawe broke the world record at 1:59:30.