The original /24 subnet falls in the first 256 IPs of the /23. Device 1 has static IP settings and is not really controlled by IT, so the mask didn't get updated in the conversion to a /23.

When you use a 32-bit mask, it isn't really a 'subnet mask' anymore. It won't ever be used to mask off an address and a 'network' with one host isn't a network. It is more of an indication to the ...