I believe this is a form of protest some subreddits are doing against Reddits announcement that they plan to charge for use of their API or something. And this effects some apps people use for viewing reddit like Apollo, which is a free app that seems to not charge any money or run any ads (and as far as I know makes no money).

It should be noted Apollo also happens to filter out Reddit's own ads, which I assume influenced Reddits decisions here. Not sure though thats mostly speculation on my part. And to be honest im not really sure what side im on either, I dont use Apollo or any third party app to interact with reddit, so im not really effected. I think a nice compromise might be Apollo just putting up Reddits ads, but I dont think reddit has indicated that that would be enough anyway.

Also, currently, when you search bitcoin on reddit, the /r/bitcoin subreddit doesnt show up. But the /r/btc subreddit (which is the bitcoin cash subreddit) does show up. To me this seems less than ideal.

And this seemed to start yesterday I think. I think on Sunday I could access the subreddit. On Monday it was closed and they said it will be open again on the 14th, which should be tomorrow, Wednesday.