If the system is under NetApp support, you can simply call the NetApp support.
You mentioned : When I started the process of transferring 9.5P6 image over, it was successfully transferred. After this, had the Node rebooted (clean shutdown) in order to boot with the intended image?
What is the currently set default image?
::>system image show
Set the default image to intended ontap version
::> system node image modify -node <node> -image image* -isdefault true
Default Image Changed.
Do take-over and give-back Or if you can afford downtime simply give it a reboot.
Please see this kb: