I'm at The Wild Detective and asked them about the no wifi weekends. It is something they do to encourage people to disconnect. They do not plan on bringing it back. A few building down is 'Serve'. They have coffee and Wifi on the weekends.
I believe the "no wifi on the weekends" is intentional...I wouldn't expect it to come back...not sure about other places?
Thanks! Your answer is awaiting moderation.