expand.js

function expand() {
  var ss = SpreadsheetApp.getActiveSpreadsheet();
  var sh0 = ss.getSheets()[0], sh1 = ss.getSheets()[1], row_counter = 1;
  // get data 
  var data = sh0.getDataRange().getValues();
  
  for(var i in data){

    // APN
    var apn = data[i][8];
    if(typeof apn == "string"){ // it's a string, let's split and iterate
      var apns = apn.split(",");
      var r = apns.length; // how many apn rows?
      for(var j=0; j<r; j++){ // loop through that row

        for(var k=0;k<data[i].length;k++){ // set up the columns
          if(k==9){ // set APN
            sh1.getRange(row_counter, 10, 1, 1).setValue(apns[j]);
          } else if(j>0 && k==10) { // ignore acreage
            sh1.getRange(row_counter, 11, 1, 1).setValue("");
          } else { // fill in the rest
          sh1.getRange(row_counter, k+1, 1, 1).setValue(data[i][k]); // copy and paste the rows
          }

            
        }
        row_counter++;
      }
    }
    else { // it's not, let's just copy it over
      for(var k=0;k<data[i].length;k++){
        sh1.getRange(row_counter, k+1, 1, 1).setValue(data[i][k]);
      }
       row_counter++;
//      sh1.getRange(row_counter, 1, 1, data[i].length).setValues(data[i]);
    }


  }
}