Package check result: NOTE

Check: CRAN incoming feasibility, Result: Note_to_CRAN_maintainers
  Maintainer: ‘Jonathan Keane <jkeane@gmail.com>’

Check: compiled code, Result: NOTE
  File ‘arrow/libs/arrow.so’:
    Found non-API calls to R: ‘Rf_findVarInFrame3’, ‘SETLENGTH’,
      ‘SET_GROWABLE_BIT’, ‘SET_TRUELENGTH’
  
  Compiled code should not call non-API entry points in R.
  
  See ‘Writing portable packages’ in the ‘Writing R Extensions’ manual,
  and section ‘Moving into C API compliance’ for issues with the use of
  non-API entry points.

No changes to worse in reverse depends.