I’ve had a bit more experience with this issue. They’ve been several instances where I’ve had to reboot the iPad in order to get the keyboard working again.
This has something to do specifically with the trackpad on the new Magic Keyboard for iPad, and how it interacts with the iPad. It is purely the trackpad that stops working, when the issue arises. The rest of the keyboard can continue working completely normally.
Also, Ive now had several instances where the scrolling is not laggy, but completely non-existant. There will be no cursor, when you try to use the trackpad. It’s as if the trackpad wasn’t there. Lifting the iPad off and replacing it did not sort the issue. I had to lift it off, shut down, restart, then replace it on the MK. Only then did it go back to normal.
I don’t know what this is, but I’m pretty cheesed off about it. I expect better from a £350 keyboard.