Ok, I've tried uploading the firmware bin file directly to the board and installed the update from there, this appears to have worked. I will run through some print tests and hopefully it's all working correctly now.
[edit]
Having run a few test prints at different layer heights, it seems the latest beta firmware 99% resolves the artifacts issue I was having with 3.5.3. There is still a very faint hint of artifacting in a few areas but not enough to be an issue for my prints.