Where did the iOS binaries go in 4.23 preview 5?

I was testing iOS builds in 4.23 Preview 4 when Preview 5 popped up just today. I had been encountering some problems so I updated to preview 5 to see if they were covered by any hotfixes, however, when I updated I was no longer able to build to iOS at all.

When I checked the options drop-down from the epic launcher, iOS is no longer listed under Target Platforms. Uninstalling and Reinstalling yields the same result, iOS is no longer listed under Target Platforms at all.

Is this a bug? Was it intentional? Is there a workaround?