What happens to raw honey after the expiry date? Will it be edible?
It is probably a best-before date (possibly regarding crystallization of the honey or other cosmetic changes), and should still be edible afterwards. 

Most honey has historically been stored raw, it is still sold in the comb in places, and has still been known for having a long shelf life if left in a closed container.  Honey has mild antiseptic qualities, and too little water, for most anything nasty to grow in - usually the heating and other processing has more to do with appearance and texture (crystallization and cloudiness, and also batch consistency and efficiency), rather than specific safety concerns.  And if it does go bad, from exceedingly poor storage, too much moisture, or something of the sort - it should be very apparent, and on the surface only.

That being said, if you have concerns about your honey specifically or believe that its raw nature poses more risk - you should act as it seems safe for you.  Putting the honey in the fridge should double the shelf life, at least, though it will also encourage crystallization.