Likewise, starting today upon my arrival to work, I have been unable to connect to my office's open guest network. This was after I updated my phone over the weekend. I think I occasionally encountered the same "your time has exceeded a limit" type message last week as dstke was encountering, but it didn't inhibit my ability to connect to the wifi.
So I attempt to connect to the open network, and then open the sign in page (notification pops up or I open the network details and select to sign into the network) and am prompted to agree to the terms and conditions on a pop up page. I selected the check mark and click to continue, and then am sent to the error page with the upside down bugdroid and the same error
net::ERR_BLOCKED_BY_PRIVATE_NETWORK_ACCESS_CHECKS