I'm running El Captain 10.11.6. I've recently tried to update to Safari 11 as I had done in several other machines with the same setup. Safari 11 downloaded fine but something went wrong during reboot and I ended up reinstalling El Captain 10.11.6. Now I'm back to Safari 9 but App Store thinks that I've already installed Safari 11 and so no longer offers Safari 11 as an update.

I assume that this will fix itself if and when a new release of Safari 11 comes out.

Can I fix this otherwise in the meantime?