I had installed a different version of regional MOM6 onto that environment which I had been using without problems for a few weeks. I am very sure I didn’t do it in a clean way which explains why it is now broken! I would like to carry on using this version, rather than the version on the xp65 envs, I just don’t know the best way to do that?
As a side note, switching into the new xp65 managed env’s wasn’t working, I was getting the same issues as Paul in this thread Running xp65 analysis on ARE and had to delete some conda files and alter my .bashrc file to get the new envs working!