What happened to with the alternate installer in Ubuntu 14.04?

The alternate installer has been ended. Full disc encryption is now possible via the "normal" one.

There is an alternate installer, provided by the Lubuntu devs. Other options for download are available at the Ubuntu CD image repository. Since alternate images are still being built for Lubuntu (as of 11-Sep-2014), I'd imagine you'd have this option at least for 14.10.