Hey Reginald, thanks for the reply.
I am thinking I may have recorded overlapping takes somehow, it seems like there were two takes stacked on top of eachother in the one takelane. I managed to get it working as expected, I'm not sure if I had a brain melt or if there is some change to the workflow recently that I need to figure out.
If it happens again I'll try and document it more carefully and establish if it's truly an issue that needs to be reported.