I've had a handful of premiers with "sticky" zones
You program it to "X" but it behaves as "Y"
eg- walkthough zone that goes into alarm during entry, (& when you check its deffo programmed correct)
program it off, come out of engineering. Go back & put it back to walkthough & its fine
I've experienced the same thing with other panels (either a optima+2, 9800 or TS790 forget which or maybe all?)