Mass attempted replication of old findings of LLMs with new models

A Zou group project retested 50 widely cited LLM findings on 20 models released between July 2024 and September 2026. By fitted trends, 44% of claims are expired (effect at or below a fifth of the original), 34% weakened, 16% persist and 6% strengthened. Capability failures such as fabricated citations faded fastest, while sycophancy and judge self-preference held. Expired claims lasted about 15.7 months on average. Each claim uses one minimal design, some models are substitutes, and individual models can still diverge, so findings about older models need retesting.