What will happen if I downgrade ios to 9.3.5?

[iMore Question]

I want to downgrade my device from 10.1.1 to 9.3.5 and everytime I try to do so I get an error i.e. error 3194. I seared about 3194 and it says you should use another pc but even after switching pc I'm unable to restore.
moreover I'd like to know that what if I install an unsigned version of iOS as apple has stopped signing 9.3.5

 

[kch50428]

One Apple stops signing, there's nothing you can do... It won't install.