https://www.theregister.co.uk/2019/04/29/sky_bricks_broadband_hubs/

Sky Broadband has rolled out a firmware update which is bricking users’ broadband hubs if they are not set to use the ISP's default choice of domain name server.

Sky customer support has been offering contradictory information to users and offering either a roll-back or a firmware fix but this is expected to up to a week.