Snappy script not working on post IPF 2.9 Sentinel 1 data

I have a very basic Snappy script which bulk processes all Sentinel 1 files in a specified folder. It works perfectly for all imagery acquired before 13th March 2018, but any imagery acquired after this date throws the following error:

java.lang.NullPointerException
Traceback (most recent call last):
File “/home/rus/snappytest.py”, line 30, in
graphProcessor.executeGraph(graph, ProgressMonitor.NULL)
RuntimeError: org.esa.snap.core.gpf.graph.GraphException: [NodeId: ThermalNoiseRemoval] java.lang.NullPointerException

I assume this is due to the IPF standard change, but what do I need to change in my script / Snappy setup to make it work with the newer imagery?

I am running SNAP 6.0.6 through an RUS virtual machine.

Any help would be much appreciated - thanks!