Read the manual and/or instructions and important notes! Everywhere it says you need the same version of the desk and the app! Disable automatic updates on the ipad so you don’t run in version problems!
+1 to that.
I would not dream of updating any software without reading the “read me” notes and having a rehearsal with the newly updated mixer or any other equipment I use to make a living. I was caught out this way in a similar situation years before software driven kit was thought of, (replacement microphone had new improved connector, non compatible with the old version!)
Thank you eotsskleet for the warning about auto updates on iPads etc. That is a good tip!
I agree with timhum. Never apply a firmaware update just before a gig without first having tested what the update will do. I had a gig on Friday and although 1.6 had just been released, I resisted applying it for fear of having a broken mixer.