Arguably the most interesting forthcoming Windows 10 features that Microsoft showed off at its Build developer conference this year were "Timeline" and "Pick Up Where I Left Off." Timeline lets you both go "back in time"—to recreate prior working environments and restore opened documents and files—while PUWILO would enable a working session to be moved between devices—for example, migrating that half-written e-mail from your phone to your PC when you get into work.
The assumption was that these features would be part of the Fall Creators Update (FCU), the next major Windows 10 update that's scheduled for around September this year. But Microsoft has now confirmed that that's not to be the case after all. Joe Belfiore, in charge of the Windows Experience and Edge browser, tweeted that Timeline won't be in the FCU after all. Instead, it'll be included in preview builds some time after the FCU release.