Hi, and welcome to the forums.
I'm no expert on VM, but there is a lot of discussion on here of the BQMs for their connections. Yours looks remarkably good for VM, so the problem looks to be elsewhere rather than the connection itself. Perhaps between your device and the VM router.
The yellow basically indicates that some traffic instigated by you is going on, with the return from the BQM ping being delayed for varying amounts while the router does its primary job, handling your data transfers. Pings and responses are bottom of the priority pile for all data transmissions. The steady green and blue are normal as long as they are normally at some steady level like yours.
That said, a connection drop on xDSLx
rather than VM "cable" is always obvious from red spikes dropping from the top, usually right to the bottom and wider than your yellow ones.
I might be a good idea, rather than post a full single day link, to put the "Live" link in your signature in your Main Site profile. That let's everyone automatically able to see what is happening before and after your post if you make it when the problem is happening
That's about all I can help with, sorry. The VM experts will be around before long, but Sunday night is often occupied doing other things. Particularly the day before further Covid restrictions are due to be announced
. As Boris put it, becoming more and more "convivial" in pubs and restaurants before 10pm.
My broadband basic info/help site - www.robertos.me.uk.
Domains, sites and mail hosting - Tsohost
Connections: OnePlus 8 Pro max 165Mbps down, 24Mbps up on Three, and B311 4G, tbb tests normally 35-45Mpbs down, 65Mbps off-peak, 9-24 up.
To argue with mindless bigots is foolish.