This weekend I updated the project to 4.11 for the marketplace submission. There were a few changes made to the engine that meant I had to fix some stuff, but it was mostly painless (there was a noticeable shift in the transparent particle material lighting that I now have to compensate for, and some audio changes needed).
One benefit is the new cut outs system, which is significantly less wasteful for rendering sub-uv particles - but I have to set up each particle emitter manually to use this, so that will be a bit mind numbing (I’ll put that off for tomorrow!).