Lots of latency?

My BQM My Broadband Ping

I didn't used to have such blocks of high yellow latency. I'm also sure they didn't almost disappear in the early hours. Does this explain why I feel BritBox / Netflix is taking longer to start a stream in the early evening?

Zen BTW and I'm in the Central Belt (Scotland) and always seem to route via London, not Manchester. Not that I've ever cared! Also, AFAIK, I'm on Zen's TTB backhaul and have been for a while.