The number of bugs that people are reporting is much greater than I was expecting, and I really can't ethically take money from people when the game is not of a sufficient quality to justify that.
I intend to use the Early Access period as a free-to-play open beta to allow me to find and fix bugs.
Anyone who has purchased the game already should be able to get a refund through steam, and anyone who has not purchased the game already should wait until steam updates the price on their end (I have to wait for a steam representative to do this).