The VoltBuilder servers are now using Xcode 12, the latest update from Apple. This allows you to build apps for iOS 14, which was released last week by Apple.
You don’t need to make any changes to your project to use the new release: all VoltBuilder jobs are now processed using it.
Before we went live with the new release, we tested by processing an entire day of iOS builds. They executed cleanly, with the same results as Xcode 11.7. We don’t anticipate any problems for you with the new release, but please let is know if you spot anything.
The latest version of Xcode supported by PhoneGap Build is 9.2.
The full blog post is here.