Definitely raises an interesting question. Are they using launch benchmarks for Opus 5.5, or Oopus 5.5 from this week?

Normally I would say "just check against the original Opus 5.5 benchmarks" : https://www.anthropic.com/claude-opus-5-5

...but most of the benchmarks don't line up anymore because the benchmarks have changed.

The Humanity's Last Exam result matches the initial announcement, though.