Except it wouldn't be a great big blow, because you'd get that penetration into the German lines, and then your follow-up is nonexistant. The OTL Englishmen can't really be counted on to move up, because the equipment loss is flatly unsustainable. Every bean and bullet is now an American beam and bullet, and switching those supply lines to route from American operational links (especially when there's a good chunk of stockpiled equipment that was built up in England specifically as fast response to frontline shortages that's now gone) is gonna take time that's honestly best spent breaking out the tactical and strategic air to just end the damn thing quicker.
Honestly, I'm curious to see how 2019 Britain handles the responsibility they've inherited at this point in time. There's a lot of growing back up they'd have to do, and I'm curious to see if they could get it done before their knowledge disseminates to everyone else and they're eclipsed.