Thread is pretty old. Replying to assist someone else.
First thing is to put in a rule to allow connections to your new IP Address. Example:
scope system
scope services
enter ip-block 172.16.200.0 24 https
enter ip-block 172.16.200.0 24 ssh
exit
commit-buffer
Now you can change the IP. Note that it will disconnect any Web sessions you have going on the old IP.
scope fabric-interconnect a
set out-of-band static ip 172.16.200.249 netmask 255.255.255.0 gw 172.16.200.1
commit-buffer
exit