Originally Posted by Marv
They're no longer spin-offs.
There are two franchises: Wolverine & the X-Men. Days of Future Past is the second film in this new franchise. First Class was the first. There will be a third and yes it will be set either in the 70s or 80s. The franchise that starred Jackman, McKellen & Stewart is done. The only reason we get to see that expired ensemble once more is that its pivotal to the story Days of Future Past is trying to tell.
The studio isn't killing their new franchise by letting go of the old one. They're using the old one in this film to sell the new one. First Class didn't do well at the box office. Days of Future Past probably will and the third film down the line probably will too.
Gee, it must be nice to be Bryan Singer's best friend and have knowledge that hasn't been released to the public yet...