High Levels of Packet Loss and Increased Upload Latency after Upgrading

[QW]

Was previously on BT Fibre 1 Package and roughly getting the specified speed of 50mbps on download. I had 0 problems when gaming - low ping and no noticeable packet loss. The only downside being that game downloads weren't too fast, but it was very manageable.

My contract recently ended and I had the opportunity to upgrade to Full Fibre 100 for a minor extra cost, and overnight gaming and regular video streaming has become unbearable. The speeds that I get are exactly as described,  but due to packet loss they may as well not be functioning. 

My guess is that when switching from my old plan to the new, I stopped using the copper cables and that has now somehow made my internet worse, are there any solutions to the issue I'm facing?

[QW]

It seems to happen on random days now, but when it does it's the whole day or longer. Could it possibly be weather?Pingplotter indicates an issue, but I don't know specifically what it is. Any help?