Warning when using pages field to sort bibliography

I have a great number of citations from a single author in the same year and to process that properly, I created my own custom sorting scheme in biblatex (style windycity). I seems to work as intended, but it nevertheless gives warnings about my use of the pages field. I am wondering if I’m doing something wrong, or else if I can turn off the warnings as it obscures more important warnings.

MWE:

documentclass{article}
usepackage[style=windycity, 
    uniquename=false, 
    sorting=nytvp, 
    date=year
    ]{biblatex}
    DeclareSortingScheme{nytvp}{
        sort{
            field{presort}
        }
        sort[final]{
            field{sortkey}
        }
        sort{
            field{sortname}
            field{author}
            field{editor}
            field{translator}
            field{journaltitle}
            field{title}
        }
        sort{
            field{sortyear}
            field{year}
        }
        sort{
            field{sorttitle}
            field{journaltitle}
            field{booktitle}
            field{title}
        }
        sort{
            field{volume}
        }
        sort{
            field{number}
        }       
        sort{
            field{pages}
        }
    }
bibliography{biblatex-examples}
begin{document}
    nocite{*}
    printbibliography
end{document}

gives 102 of the following warnings when running biber:

WARN – Unknown field ‘pages’ found in sorting template