I can't find an answer to this, just other annoyed people who have stopped using MacsFanControl because of the lack of an option to stop update notices.
Macs Fan Control is brilliant and has let me get control of the unnecessarily overactive fans on my good old MacBook Pro. I've got it set up just right to keep things ticking over at a good operating temperature. But the update notices are really, really annoying.
I have the latest MacsFanControl version my computer and OS can use. (1.4.6) . My computer runs OS X 10.11.6 That's the last OS for Apple produced for my 2009 MacBook Pro.
So I don't want, need nor can I use a later MacsFanControl "update". Yet every time I log in or restart up comes the update notice. It wastes my time and worst of all MacsFan (which I have as a login item) has to be manually started.