Thank you, the "thing" you mentioned I've seen somewhere in the topics I read, I need to search it again for sure. Keep it simple for my understanding that process is to block my wii U to be automatically update firmware and loose hack ability isnt it?
P.s: Normally what do we call wii u version and custom version (for hack) like we call ofw and cfw for Sony stuffs?
Yes exactly this, you don't want your Wii U to update through sleep mode or other means, so blocking servers will prevent that. Happy hacking!