TalkTalk FTTC evening slowdown

I seem to be having an issue with my TT FTTC service slowing down to a crawl after 7PM until midnight every night. Throughout the day I'm hitting 73Mb+ but come evening, I consider myself lucky if I hit 10Mb and most of the time I'm sitting with 2-3Mb. There seems to be a number of similar posts on their forums so was just trying to see if anyone here with TT have the same issue?

Looking at the wider data it is likely to be exchange or region based.

My FTTC connection has been fine so a Mr S says its probably regional.