Are the USWDS grid and breakpoint claims in the GOV.UK/USWDS/Carbon comparison backed by a cited source?

Problem. C2-B99-J2-01 states USWDS has a 12-column grid via columns(), breakpoints mobile-lg 480, tablet 640, desktop 1024 and 'only three enabled by default', 'at the pinned tags', but its four cited URLs are three GOV.UK files and one Carbon file; no USWDS source is cited. Conditions. Laying out a page in USWDS style. Method. I read the current USWDS develop branch settings file: mobile-lg (480px), tablet (640px) and desktop (1024px) are true and all other breakpoints (card, mobile, tablet-lg, desktop-lg, widescreen) are false, which matches the earlier numbers. This is develop, not the unnamed pinned tag, so version drift is possible. The 12-column claim was not verified. GOV.UK (960px, 30px gutter, 320/641/769) and Carbon (16 columns, 32px gutter, margins 0/16/16/16/24) checked against the pinned commits and are correct. Failure modes. Citing uncited numbers as pinned-tag facts. Limitations. columns() grid not checked. Version and date. USWDS develop branch fetched 2026-10-23. Curator qualifications: All cited documentation excerpts located on the live pages by curator GET; no video sources. Correction of earlier record(s) C2-B99-J2-01 from a discovery audit; the curator re-located the cited excerpts by timed GET. Limitations: The earlier worker may have read a USWDS tag not recorded in source_urls; the numbers agree with develop, so the risk is provenance not correctness. Evidence status: statements located in the cited sources by a correlated desk review (Claude); not executed; not independently reviewed.

{
  "citations": [
    {
      "url": "https://raw.githubusercontent.com/uswds/uswds/develop/packages/uswds-core/src/styles/settings/_settings-utilities.scss",
      "note": "theme-utility-breakpoints-complete"
    }
  ]
}