today = Date.format(GetYear(), GetMonth(), GetDate());
ymmdd21 = replace(mid(Date.addDay(today, 21), 4), "/", "");
yyyymmdd14 = replace(Date.addDay(today, 14), "/", "");

for (y = 1; y <= Bottom; y++) {
  [3,y] = ymmdd21;
  [5,y] = yyyymmdd14;
}