I have several Sungold tomato plants that have recently developed dark brown mottling on the lower, older leaves, and from what I have read on the web, I reckon this is most likely Early Blight. Like the fool I am , I neglected to clear the remnants of last years tomoto plants from the garden until about February, so I am guessing that's where it came from, but is there anything I can do about it? Or are these plants destined for the bonfire?

Please give me good news!

Well you already know what you did wrong to get early blight so here are
three fungicides to help control or eliminate early blight. You may be
able to find these fungicides at a gardening center in the UK, that is
if there are gardening centers in the UK, I'm not familiar with your
country just with your Tony Blair, Bush's sockpuppet . These are the
fungicides that may help you out, Bravo (chlorothalonil), Dithane
(mancozeb) and Quadris (azoxystrobin) I hope you're able to save your
tomatoes. Peace and good karma to you. Ed