Layoff notice, what does the 60 days mean? - what worked for you?

My employer announced that the site will close and gave us written notice. There are 4 people counting on me, so I am trying to be careful. Some colleagues are already leaving. Should I stay for the bonus?

Start your search early. I wish I had begun the day of the notice.

I stayed for the retention bonus and looked for work on the side. It cushioned the gap.