Eurotunnel warrants are weird - it's 3 warrants to a share, plus the conversion premium requires a payment in both Sterling and Francs (presumably Euros,now)
Looking at the intraday chart, it's actually quite usual(!) with these - the bid doesn't move, but the offer goes up a hundred-fold - not sure if this is to discourage buying, or just some idiot getting the point in the wrong place!