I believe that mod to make the unit "On-Air" is a requirement of those wishing to use the Pluto without a computer but putting out a signal when when powered up. So useful for the portable guys. There was a post about it on the forum some time ago, I forget the title of the thread.
Thanks for the update in the firmware regarding disabling the spectrum, I mentioned that to F5UII a few days ago, if you are using the PlutoSDR for 70cms or for 23cms etc from home you will also be typically connected to the internet some times to arrange comms or use Skype etc as talkback, in these situations the Spectrum is not wanted as it could be a distraction, or simply taking bandwidth from a slow connection etc.
I am very grateful for the people developing the software and can appreciate that it is generally QO-100 that is driving the updates, modifications and general thinking. The satellite is probably the greatest driver for Amateur TV going at present. So don't mind the gripes every now and then, from this end I really do appreciate the people that can, and are doing the software for it.
Cheers
Adrian