Hi, all sorted.
Turns out my version of adrotate pro was not compatible with the new version of regular adrotate.
I updated adrotate pro via my server cpanel and all is now well.
Question for you, seeing as you know about this sort of stuff:
How come adrotate will update the core plugin via the wpress panel but for pro you need to use FTP on the server?
I had been assuming that each time I updated both of the adrotate plugins via the wpress panel that they were fully updating both?