Actually its NOT the auto names array that you want to alter… Thats a list of names that the app will by default will create ( based on doc content ) The script goes and finds these files and changes the names afterwards…

This should do you… I updated it a touch… And made it simpler to edit…

#target illustrator
 
 
artboardsToPDFs();
 
function artboardsToPDFs() {
 
    if ( app.documents.length == 0 ) { return; }
 
    var aiOpts, artBds, baseName, doc, fileDef, fileRep, i, names, obj, saveFile, saveFold;
 
    doc = app.activeDocument;
 
    baseName = doc.name.replace( /.ai$/,'' );
 
    saveFold = Folder( Folder.desktop + "/AI PDF's" );
 
    if ( ! saveFold.exists ) { saveFold.create(); }
 
    artBds = doc.artboards;
 
    names = Array();
 
    for ( i = 0; i < artBds.length; i++ ) {
 
        obj = Object();
 
        obj.defaultName = baseName + '_' + artBds[i].name + '.ai'; // Default AI naming convention
 
        obj.replaceName = artBds[i].name + '-' + baseName + '.pdf'; // Script swap about
 
        names.push( obj );
 
    };
 
    if ( ! doc.saved ) { doc.save(); }
 
    aiOpts = new IllustratorSaveOptions();
 
    aiOpts.compatibility = Compatibility.ILLUSTRATOR13;
    aiOpts.pdfCompatible = true;
    aiOpts.saveMultipleArtboards = true;
 
    saveFile = File( saveFold + '/' + doc.name );
 
    doc.saveAs( saveFile, aiOpts );
 
    doc.close( SaveOptions.DONOTSAVECHANGES );
 
    saveFile.remove();
 
    for (  i = 0; i < names.length; i++  ) {
 
        fileDef = File( saveFold + '/' + names[i].defaultName );
 
        if ( fileDef.exists ) {
 
            fileRep = File( saveFold + '/' + names[i].replaceName );
 
            if ( fileRep.exists ) { fileRep.remove(); }
 
            fileDef.rename( names[i].replaceName );
 
        };
 
 
    };
 
};
 

Larry you need to have named your artboards first… It looks like yours are AI defaults… If I recall corrrectly this was always the case for Tim…

Yeah, I didn't need to bother myself with testing for Tim… Named artboards default to strings, un-named to digits never tried with mixed…? Did it work OK once you named them?