Thing is, if you look up the "power and pitch" settings, for UAS, they tell you to set figures that are almost exactly what you need to continue 'as you are'.
So, if you are at FL350, doing .78 and set the pitch and power in the table, you will still be going along much as before.
Now, while we can all see the value in this, I'd suggest you need a power setting that is safe, and start on down straightaway if practible.
I'd set a medium power setting, one that I know would prevent stall and overspeed. This would work nicely at low altitude.
If it happened upstairs, my choice would be the same, and descend.
If for some reason, you couldn't descend, then the numbers in the table are what you need.