BritBox just sent me this message:
I highly appreciate your patience on this. BritBox is currently experiencing a service disruption. When signing in, searching or playing shows, you'll see an error message or unexpected behavior, such as being signed out. We're working as fast as we can to restore your service, and we're sorry for the interruption. As of the moment, we have already noted some concerns that does have the same issue. We are already partnering with our technical team and we will get back to you the soonest. We are already working on with the team regarding the issue and we will send you an email correspondence once the issue is resolved. Thank you for reaching our and I hope we have it sorted out the soonest. Stay safe and take care always.