Javascript:
I have object cell with something date
params.date = cell.getDate();
params.timestamp = cell.getDate().getTime() / 1000;
console.log(para
params.date = cell.getDate();
Returns the DATE not the TIME.
params.timestamp = cell.getDate().getTime() / 1000;
is converting the date into a date+time - not reading the current time.
But even if you get the timestamp in javascript, the output of PHP's date function will depend on what timezone it is in.