strange output of julian.JDEToDate

[hjy1210]

function oddJDEToDate(){
  let d = 1721790.0684809217
  console.log([julian.JDEToDate(d), julian.JDEToDate(d+0.5)]) 
}
oddJDEToDate()  // [ 0001-12-31T10:42:33.414Z, 0002-12-31T22:42:33.428Z ]

Note: Difference between julian.JDEToDate(d) and julian.JDEToDate(d+0.5) is more than one year.