It was a bit confusing the way that image puts it but that's not what epic levels are changing to, that's how much extra hp you'll get from epic levels with the full 100% increase to level up hp with combat style feats. Combat styles will now grant 25% more hp from level ups per feat, up to 100%, with epic levels scaling at half. So all of those hp values are being added flat to what we already have in game so that -50 is a +50, and we also get +(anywhere from 120 to 240 hp depending on class's hit die size).