Here is the latest news:

Q: Is today truly the day for OLSB shut down. No plans to delay it?

A:: OLSB will continue to run through April 30, 2012 (Redmond, WA time). Tomorrow, we will start closing the service down site by site. We’re continuing our commitment to helping ensure a straightforward transition by arranging for custom email hosted through Windows Live Hotmail to still work for up to six months and providing a support form users can submit to recover OLSB data if they missed today’s deadline. This form will be available in the OLSB Community tomorrow (May 1)

I suggest you do this:

You have to rebuild your OLSB website on O365. So you need to save your OLSB website content before it is deleted.

The best thing you can do, is with your browser, visit every page of your OLSB website and Save As... (or using ctrl s key) each one of them to your computer.  You can't upload that, you just will have a copy of your website content on your computer because they are going to deleting in a few hours.