change start time to UTC time fo run in console browser

Question

i want to change time of this code to UTC, but when i changed the code error occurred.

var timerId;

 start = new Date().getTime()

   execTime =new 
   Date().setMinutes(43,30,000)


    var t=setTimeout(() => {

    count = 0

    timerId = setTimeout(() => { 
      document.querySelector('button.buy').click();

        console.log(0);  
  
    })

}, execTime - start)

Im sorry i wrote this with mobile. thanks for help