At first thought there may be a way to spoof the iOS version. I remember seeing it done before for a different reason..... Now that you bring it up, I'm on 9.0.2 and wish I could update my watch..... Only problem I foresee is that 9.3 actually has things in it that allow the updated watchOS to work right. In the end, spoofing the iOS version may be possible, but I'm sure he'll run into other issues with functionality. Hopefully someone else chimes in. Best of luck