Bad latency playing COD

Hi All

Hope everyone is coping in these strange times?

New to the forum. My issue has led me here after trawing the net for a possible solution.

My ISP is Sky and after calling them numerous times over the last 12 months and recieving a new router the problem still persists...my ping is high most of the time no matter what time of day it is.
Sky told me they can do nothing about the ping.
It's wierd though, because the bad ping seems to last for around two weeks. Then I have no issues with game lag for around the same period. So a two week cylcle.
It had been bad in the afternoon yesterday, but last night was totally unplayable for the first time.
I started the BQM yesterday and here are the results.

My Broadband Ping

I'm not extremely knowledgeable about the topic, but know a bit. I also know this can be a dangerous thing

Can any one of you knowledgeable people decipher the graph and confirm that this is not in my head?
If there is an issue, is there any way to fix it? I know this sort of thing is a bit of a black art and after reading a lot on the net there doesn't really seem to be a solution and ISP's must be fed up of cutomers contacting them about this problem.
I have already tried opening the ports on my PS4. Setting the PS to a static IP eic and bought a Netgear XR500 gaming router and read tonns of tutorials on how to get rid of ping until my head hurts, but nothing has worked. My only conclusion is that there is an issue with line that Sky are not willing to admit.

The 8pm jump in latency is either a big change in Sky's routing due to a failure somewhere or it is the DLM applying Interleaving.

Low interleaving adds exactly 8ms latency. That looks right what your ping jumped by at 8pm.
Nothing Sky or any ISP can do about the DLM or interleaving, it is an automated process with no manual control.

The question that needs answering is what are you doing when the graphs are showing yellow?

How fast is your broadband? As if trying to game when others are using social media and web pages or streaming video then their activity can have an impact on latency.

The baseline (green) has risen to around 20 ms but that should not make for a bad gaming experience.