Upgrade from 9.3.0 to 10.0 questions

Thanks guys. Let me throw this out there as well and see if it makes any difference in what you've already suggested:

 

 

My plan is to upgrade the standby unit after hours while there will be no traffic flowing through them. Once that unit has been upgraded to 10 I will failover to him so he becomes the active unit. At that point my Management team would like to wait and make sure traffic flows as it should the next morning. If the traffic isn't flowing as expected we'd fail back to the unit still running 9.3. If all is well I would perform the upgrade on the other unit that was initially the active unit.

 

 

Does that make sense and sound reasonable?