Two and a half months, actually. Which is still a lot less than the lifetime we were promised (unless you're a fruitfly or something, I guess) but you have a little longer to migrate your stuff.
I suspect this cuts right to the core of "why" Joyent would dump pretty low-overhead services and catch the flack over it. The hardware requirements to provide this shared hosting environment has plunged over the years; it's part of why I disagree with the "why did you EXPECT a lifetime deal" folks - because I always assumed that such a level of service would get cheaper and easier.
Except the one thing that doesn't get cheaper is the human power needed to administer the stuff and deal with the people. And as Joyent moves away from that sort of thing it becomes an unusual task and a drain on core business.
Which doesn't mean I think this is okay; the smart thing would have been to hand all of us lifetimers a lifetime bottom-tier slice. But I see why they'd want to be out of shared hosting.