Yes, fail all instances to one node.
Go into VCS cluster console and for all cluster groups place them into Freeze-Temporary
Once this is done reboot all passive nodes and then run the SP4 exe with the /Passive switch.
Once all passive nodes have been updated failover the instances to the upgraded node.
Now run the SP4 exe with the /Passive switch on the final node.
Unfreeze all cluster groups.
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"Ya can't make an omelette without breaking just a few eggs" 😉