Frequent SEVERE Client Lag, High Ping (500+), 3+ second delays, and ruberbanding

I've recently come back to find that I occasionally experience severe client lag (client taking over 5 seconds to register me clicking on things), and much more frequently (at least 2/5 games) my ping spikes up around 550ms, and I get 3+ second delays on inputs, severe frame drops when almost anything happens (auto/ability/spell cast), and sometimes severe rubber-banding (champ returns to where they were 3+ seconds ago) - I've even experienced this in the practice tool and tutorial.

I have a fairly decent PC (Ryzen7 2700, 16GB ram, 1080Ti) that runs nearly anything at or above 60fps on ultra settings, and as such these are issues that I am only experiencing in LoL, and I see a lot of other people have been reporting having these same issues since 9.23... [zombie-brand-mindblown]