I apologize in advance if it has been asked several times already, but this thread is humongous, but I have just installed a9lh and Luma3DS CFW using the DSiWare Downgrade, so I started on 11.1.34 and now I'm 9.2.0, is it really safe to update my 3DS firmware (I'm on a New 3DS if that makes any difference, which I think it shouldn't)
Yes it's safe.