If it's already updated to JB then it's a bit late to try to stop it. Any other notification you have about updates should be fine to continue with. They will be updates for something else and I do not know why you would not want them.
I'm not sure I can help you further because you and I seem to be talking about different things all the time. I have already described my experience. I thought my instructions were very clear, and backed up with screen prints for clarity, but if something else is going on for you then I don't know what it is or how to fix it.
As for going back to ICS, the best way I know is to download the appropriate official ICS ROM for your country/region and to flash it with PC Odin. I already said as much in post #144. My views have not changed.
We seem to be going round in circles here. I think I've helped as much as I am able and I've got nothing new to add. If that's not enough then I'm sorry. Hopefully someone else can help.