No No guys. You need the COTS update 1.1 to bring you up to the latest version of COTS -regardless- of whether you bought COTS "full" or COTS "update from the older accusim" version. Trust me.
When you bring up the flight log do you see "sm" anywhere? It means statute miles, which was a tiny little clarification only added in COTS update 1.1. If you don't have that, then you have the release-to-market version, 1.0, and you need to install COTS Update 1.1.
If you know you have COTS and still aren't sure which version of COTS, go ahead and install COTS Update 1.1. anyway!