As reported by Ben Sullivan, when running scenarios via Ant CLI, the reports are being outputted to $ANT_HOME/lib instead of target dir.
Problem stems from the fact that the FilePrintStreamFactory uses the
to identify the output dir. The classloading of Ant by default must be setting the code source location to $ANT_HOME/lib.
Need to find a way to configure Ant classloading or allow explicit setting of the output directory (currently only the entire output file of the print stream is configurable, which makes it pretty useless for running with multiple scenarios).