So...... Interesting thing for this patch with space marines. Knife wielder fast attack has noticeably shorter lunge distance than the other larger melee weapons. Heavy attacks appear all the same and do travel further than light attacks.
Been that way for many patches, there's video showing Knives for whatever reason have chode light attack lunges. Guess it's still on their to do list as I'm assuming it can't be intended gameplay.
Pretty sure all Heavy attacks have always travelled farther than a light attack lunge(and should). If SM are going same distance as Eldar now, it's the Eldar that got fixed to go down to match everyone else more likely.