It wasn't that close to defeat; British production was still out producing German in aircraft and the notion that the RAF was going to fall was bad intel, wishful thinking by the German high command or deliberate mildec. I think it's a bit overdramatic to claim the RAF was at its breaking point when most airfields remained operational and the military industry still buidling replacements. The British had solid air defense and early warning radar, international pilots, and plenty of juice left to punish the Luftwaffe.