Layoff notice, what does the 60 days mean? - 3 months and counting

My employer announced that the site will close and gave us written notice. It has been a long 7 weeks. I do not know if I should start looking now or wait for severance news. Should I stay for the bonus?

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

Write down key dates and keep copies of the notice. Mine helped when a question came up later.