Hi Andy,
There were a few issues with the way exceptions were handled that you can read about here:
https://totara.community/mod/forum/discuss.php?d=5478
The main ones fixed by this issue is that exceptions that had been cleared by an administrator would return every time the cron ran. There is also another patch in this release that fixes the behaviour of "first login".
The "major alterations" were only really on the backend, to let us store which exceptions had already been handled, to a user things are pretty much the same, except (hopefully) without the bugs!
Simon