As I said in another thread on the topic, at the time of backing there was no firm release date so Obsidian haven't broken any promise they made when you backed. Given that others paid extra to get beta access I don't really think this is a reasonable request.
Josh has replied to a post asking why there's a delay on his Tumblr. His response was "bugs". Also Obsidian's official Twitter has a picture of a calendar with someone circling the 8th of May on it. I don't think they've literally made an announcement but it seems all but confirmed.
but backers have beta since november 2017 so they get it as early as possible. I pre-order the game in Steam 2 weeks ago where was clear release date 3 april,so kinda broken promises.
