If VM are 100% at fault, utilisation (over subscribing) is their problem, then make a formal complaint with VM, after 8 weeks if its not resolved take it to CISAS, follow my simple guide to make it easier.
You can, if you provide enough evidence to CISAS you can get up to, if not more than 50% of your BB costs.
Hit them in their pocket not yours.
Also, TBH, the more that complain paints a picture to CISAS, and in turn OFCOM might get involved, it might be a small percentage, but its a big enough percentage to make heads turn.
I seem to recall that when I was going through some issues I was credited around 33% of my bill for the peak time slowdown. I believe it was that amount because my speeds were affected for 1/3rd of a 24 hour period, hence 1/3rd off my bill. That would seem to be what they have credited you because 4 months at £30 equals £120. So 1/3rd of that is £40 for those 4 months since the problems started. If your issues of slow speed are happening all day and everyday then maybe you are entitled to more. However 33% seems to be the usual credit for poor service as far as I can recall.
So if you are speaking to a tech person when you ring customer service, they usually are allowed to put through a credit for your account for the month that you are experiencing with slow speeds however can't do much beyond this. Ask to be put through to the billing team at which point you can get any credit for any months that have not been accounted for.
I believe this is around 33% of the bill as stated for each month that goes by where you have issues.
Unfortunately if you don't call and ask about the credit, Virgin Media will not just give this to you DESPITE knowing the issues in the area.
It took a year and five months for me to get my speeds back from over utilisation!
exactly the same here unfortunately' 5MB down on super fibre 50
Super Fibre 50
Average download speed at peak times (8pm-10pm) 45.94Mbps lol who there trying to kid' its pointless ringing customer services because they just fob u off saying' you get upto 50mb dont mean to say you get 50 the last person i spoke to was very rude and didnt want to know basically' my honest opinion is this crumbling network is getting ran into the ground liberty global.
I am in an OVERSUBSCRIBED VIRGIN MEDIA AREA - Contention reference F003570038, ongoing since March 2016