After that point it will not be updated again and won't be available for download.
It's important that your website is upgraded to ExpressionEngine 3 before this date.
The upgrade isn't always smooth sailing. Depending on how your website was built it could take one hour, it might take a couple of days.
As one of Europe's leading ExpressionEngine agencies, our team can provide you with a free personalised action plan on how to upgrade your site.