Why is the BBC urging log in on Echo devices?

I basically use my Amazon Echo as a replacement for a digital radio. I listen to a number of stations, some from the BBC. Lately, when I ask for a BBC radio station it says something like 'you'll soon need to sign in to your BBC account to listen via Alexa'. Why would they do this? I get it for iPlayer but not for listening to the radio live. If I listen on another device, such as in the car, …

devices echo log privacy