
AI Travel Planners Don't Know It's Winter Yet: The Seasonality Gap Deciding Your Holiday Bookings
The short answer AI travel planners are answering this winter’s questions with last winter’s data. The frontier models travelers use for trip research have training-data cutoffs frozen between January and May 2026: Claude Opus 5 holds data through May 2026, Gemini 3.7 Flash through March 2026, GPT-5.6 Sol through February 2026, and Meta’s open-weight Muse Glimmer through January 2026 (Temso AI, September 2, 2026). Ask one in October 2026 for the best hotel near Vienna’s Christmas markets and the model’s internal “memory” of that market is the 2025–26 season — last winter’s review corpus, last season’s rate anchors, and any December 2025 coverage it absorbed during training. ...