The OCA is unlikely to go away any time soon. If for some strange reason OU decided to do away with it, they would have to give lots of advance notice.
Recently i checked on thew oracle website; they had written something to the effect the OCA Certification has been discontinued and that nearest certfication is OCP.
Please provide a link and/or quote the relevant text from the web page that you refer to in your post.
Please do provide the reference link. The OCA certification has not gone away, so I'd like to correct any misinformation that may be posted.
Oracle Certification Program