Just in case you're wanting to join sooner RODE, there is an option available to you -
From the FAQ:
If you need to upgrade or refund your pledge, please contact us at firstname.lastname@example.org. We are very responsive to any of these requests. If you are not comfortable with this policy, please WAIT until after Early Access release on Steam so you know what you are buying
You may have to wait a bit as I'm sure the devs have a lot going on right now distributing keys, but this is your best bet if you want to go that route. Personally I did the exact same thing (though at the $80 level) and recently decided to go big and up to the $150 package. I've already sent another $70 and am just awaiting them to approve it and send me a pre-alpha key.
And with that being said, keep in mind this is pre-alpha, and very much still in testing. Don't expect it to be treated like a normal game release and let them do their thing. I'm sure Rob and the rest of them and working on things as soon as they can, so I'm sure they'd really appreciate our patience while they work things out. They're on it, I promise.
Hope to see you in game soon my dude!