Howdy!
To answer your questions:
- Currently, the game isn't up for single-purchase anywhere. It's only available in weekly Friday builds on Patreon and Subscribestar, since it's still heavily in development.
- If you subscribe, download the latest build, and cancel the subscription, it's still yours to keep. So long as you download the files, you'll retain access to that build of the game. Please keep in mind that the 'Play in browser' option through Patreon does require an active subscription, just because that's how Itch.io handles access to the game.
- Game codes will be distributed after the game is done, to anybody who has supported an amount equal to or more than the full price of the finished game (£10), no purchase required.