As soon as I loaded onto a service that started at London Victoria, I was averaging about 5-10fps and it was still moderately laggy until I left London. I think especially around Clapham and Victoria needs a major update so that it can run smoothly because right now the lag is just horrible. Btw I’m playing on Xbox One S
Unfortunately the old gen consoles just can't deal with it. Even the new gen are struggling at London.