Hi Nathan,
Thanks for taking the time to reply. I didn't realise that selecting 'Mark as in Progress on first view' was why this happened, thanks for pointing it out to me. I've tested it and it works exactly as you say, and I will ensure it is not selected for these mandatory courses. We just need to work out a way we can report on those who have already unenrolled so we can manually remove them.
Best regards
Sue