<h1></h1>

const h1 = document.querySelector('h1')
const date = new Date('2020-03-27 17:44').toISOString();
let timer = setInterval(() => {
  h1.textContent = new Date().toISOString();
  if (date <= new Date().toISOString()) {
    h1.textContent = 'True'
    clearInterval(timer)
  }
}, 1000)