Check the configuration, and see what the system is expecting to have on each expansion port. Remember in Manager, the control unit is Device 1, the 4 slots on the control unit are device 2, 3, 4, and 5, and expansion port 1 is device 6, and so on.

If Expansion port 4 (device 9 in Manager) is the same module as expansion port 8 (device 13 in Manager), yes you can just move the blue cable connecting the expansion module to the control unit. You will have to blank out the extension numbers on ID 801 through 815 (or 830) and recreate them on 401 through 416 (or 430)

If the type of module is different, be sure you have an offline configuration just in case. I would suggest deleting the extensions on expansion 4 (ID 401 through 416 or 430), NOT THE USERS associated with those extension ports), delete Expansion Module 4 under Control Unit (Dev No 9), physically disconnect the expansion cable from Expansion port 8, and do an immediate reboot when you send the configuration back. After the control unit comes back up, power off, connect the expansion module to expansion port 4 and power back up. You can delete extension IDs 801 through 816 (or 830) and put them back on 401 through 416 (or 430)