Floating IPs on new traffic group members

I have a situation where there are a pair of older F5s being replaced by a pair of newer ones. All devices are running 14.1. The new devices have had their self IPs for the various VLANs added but there is some hesitation as to when to add the floating IP that resides on the existing pair. My assertion is that the traffic groups and HA groups, need to be created and the new devices are added to the Sync-Failover group before the floating IPs are added as I believe that the new devices would activate the traffic group were they not in the failover group. My colleague believes that the floating IP should be added as soon as the shared traffic group is created. Is there any documents that support one position over the other?